Juan Robles and the Inquisition The Odyssey of a Sephardic Glassmaker
Fact Paper 5
© Samuel Kurinsky, all rights reserved
- The Background for the Juan Robles Story
- Juan Robles' Early Years in Spain
- Escape to Fez
- Robles' Return to Spain?
- Refuge in the Carribean
The art of glassmaking was born near the city of Ur, birthplace of Abraham, about 2400 BCE. It remained a uniquely Semitic, and subsequently a Judaic art through the early centuries of the Common Era.1 In Spain, the Jews remained predominantly the glassmakers until the horrendous massacres of 1391 ushered in a drive for conversion. Some Jews left Spain, others converted, and most others feigned conversion. Finally, the expulsion of the Jews from Spain in 1492 made the continuation of the art by professed Jews impossible.
Judaic archival material was eradicated under the Inquisition. The history of the technological contribution of the Jews to Spain has virtually disappeared.
The enlightening story of the master glassmaker, Juan Robles, was fortuitously preserved in the proceedings of the Inquisition itself.2 Juan's case was one of eight cases concerning glassmakers of the town of Cadalso de los Vidrios ("Cadalso, the Glassmaker's Town), conversos who were accused of Judaizing after having converted to Christianity. Spain lost much as a result of such persecution. The industry, "probably the most prolific in Castilla"3 suffered as a result of the emigration of glassmakers, and fell into crisis because of the subsequent persecution of the Marranos (secret Jews) of the industry. By 1548 the industry was so weakened by these proceedings that Venetian glassware was again imported.4
The Background for the Juan Robles Story
Cadalso de los Vidrios, as its name indicates, was a center where glassblowers plied their trade. The art was dominated by Jewish families who had carried the art with them from the days of glory in Alexandria under the Greeks; Thereafter they had continued the art under the Moslems in Fustat (old Cairo), from whose persecutions they fled to Moorish North Africa and eventually to Moorish Spain.
For a few centuries the Judaic masters basked in the warmth of the Spanish "golden age," in which science flourished and the arts flowered. The conquering Christians continued to allow the Jews a modicum of freedom to pursue their faith, and the freedom to practice business and the arts. It was a pragmatic policy, for the nobility needed and took advantage of Judaic knowledge, skills, and commercial acumen.
Under Alfonso V (1252-1283) Jewish officials of the court were granted houses, vineyards, olive groves, fields and mills in perpetuity. The prelates and the grandees of the court and of the countryside were no less generous. No lesser figure than the Bishop of Burgos, who also enjoyed the position of royal chancellor, became a partner of a Jewish physician and several Jewish financiers. Not only was Spain's tax structure devised and administered by Jews but even the Order of Santiago entrusted the administration of the order's vast domains to Jews.5
The city of Burgos, like Cadalso de los Vidrios, was another of the important glassmaking centers of Christian Spain, "a gathering place for Moorish and Jewish glassmakers during the late years of the [15th] century."6 All three major glassmaking centers in Spain, Barcelona (Cataluna), Toledo (Cadalso de los Vidrios), and Burgos (Medina del Campo) were likewise major Judaic centers..
An insidious canker began to spread its corrosive influence on Spanish society as soon as the Christians deployed through the Iberian peninsula. The decrees of the Lateran Council during the reign of Ferdinand III, and the spirit of the Justinian code affected Spanish law and society. The noble overseers, caught between the strictures of the church and the commercial advantages accruing from the activities of their Judaic constituents, were obliged to compromise the protection of "their" Jews with decrees that, once passed, were enforced only when ecclesiastic pressures proved it necessary. Affable Alfonso X, for example, was persuaded to codify retrogressive Christian precepts into the infamous Las Siete Partidas. At first the code was minimally enforced, but by the end of his reign, the sinister side of the process prevailed, and the first of a succession of blows was inflicted upon the Spanish Jews.7
The Jews sometimes found themselves caught between contending Christian forces. In 1366, for example, the Jews of Burgos suffered after the king's step-brother, Henry of Trastamara rebelled. King Pedro, surrounded by Judaic advisors, had been referred to as the "King of the Jews," albeit his treatment of the Jews was no less harsh than was customarily accorded to them.
"When Henry took the city of Burgos, he demanded an immense sum of money - about 1,000,000 maravedis - from the local Jews; and those that could not pay their share were sold into slavery. One of Henry's first acts on ascending the throne was to declare a general moratorium on Jewish loans. This prompted the Christians of Segovia and Avila to attack their Jewish neighbors and seize the promissary notes and pledges they had given them. When the new king entered Toledo early in May, he demanded as in Burgos, a sum of 1,000,000 maravedis from the Jews, which was to be paid within a fortnight, for his French mercenaries."8
Some Jews sought a more congenial climate; When the horrific massacres of 1391 ensued, the exodus swelled. Generally, however, Jews viewed the situation as an aberration. When the church launched its campaign for conversion, many acceded, most feigned conversion. Many more were driven into conversion, real or politic, as a consequence of the church's renewed, mare massive and virulent effort in 1412. Finally, in 1492, when no other choice was left but expulsion or conversion, most Jews left Spain, leaving their hard-earned assets behind.
Many thousands of Jews hesitated to tear themselves from their roots, hopeful for Spanish society's return to reason, or were ready to risk the wrath of the tribunal of the Inquisition should their secret adherence to their faith be exposed. Among these intrepid optimists were the eleven Judaic glassmaking families who remained behind in Cadalso de los Vidrios. The Christian hierarchy remained skeptical of the sincerity of conversos. They were dubbed "Marranos" ("swine").
The Inquisition had its commercial aspect. Greedy Christian and Moorish opportunists saw in the dire straits of the Marranos a fortuitous means of acquiring prestigious, profitable enterprises. These piratical businessmen entered into collusion with councilmen and church dignitaries to accomplish the incarceration, or worse, of the Marranos, and the seizure of their glasshouses. Denunciation of Conversos was a convenient means to that end. Accusations of Judaizing were rampant.
The new masters, however, were ignorant of the secrets of glassmaking, nor had they acquired the necessary skills to produce glassware. The former owners, in lieu of being imprisoned or burned at the stake, were often obliged to work in humiliation for their treacherous deposers.
The church did everything in its power to assure that no covert Jews could continue to exist, much less carry on the practice of the esteemed art of glassmaking. The practitioners of the art had achieved the status of nobility in France and in the two glassmaking Italian communities of Altare and Venice. The art of glassmaking was regarded with equal reverence in Spain, and had achieved a status rivaling that of Venetian glassmaking, where the art had reached a peak of renown. The glassmakers were placed in a particularly precarious position, for they were dependant upon access to forests for the vast quantities of fuel required to maintain their furnaces, and the forests were often on the tracts of land allocated to the church.
Cadalso de los Vidrios furnished glassware, both practical domestic ware and artware to the kingdom of Castile. Its finest masterpieces graced the tables and decorated the furnishings of the kings and nobles of the kingdom. The inventories of these aristocrats, as, for instance, that of King Phillip himself, show that the works of Cadalso de los Vidrios were included along with the fabulous Venetian artware, and with the equally admired works of the Cataluna area.
It is against this background that Juan Robles' remarkable odyssey is laid.
Juan Robles' Early Years in Spain
Juan Robles, son of Hernando Robles and Maria Alfonso, was born in the province of Toledo in the quiet town of Cadalso de los Vidrios). Hernando was a Marrano, whose father had been forced into conversion. Maria was likewise born into such a family, but her family had abandoned their heritage. They kept the secret of Maria's Judaic origin from her, bringing her up as a devout Christian, thus shielding both her and themselves from the pervasive inquisitorial surveillance.
Hernando, however, carried on with his Judaic faith so surreptitiously that even his wife, Maria, was unaware that he was secretly teaching its precepts to his son, just as Hernando's father had taught him. At least, so Maria later testified before the dreaded Inquisition.
After his father died, young Juan and his sister Juana were left without family on their father's side. Juan went to work for his mother's family, also glassmakers. They were suspicious of Juan's adherence to Judaic practices. Dreading that the slightest hint of heresy would place them all in mortal jeopardy, they treated Juan miserably, perhaps to drive him away. Juan faced a cruel dilemma at this traumatic time, for his ability to achieve a master's status, and therefore to gain independence, depended on access to the furnace. Juan was thwarted in this endeavor by his mother's relatives. He was prevented from working at the furnace and was given the most menial tasks, relegated to sweeping and running errands. Juan's uncle had no regard for Juan's future, and without his uncle's good will Juan could scarcely hope to attain a master's credentials. Juan bitterly left the employ of his "Christian" family.
Fortunately for Juan, the training he had received from his father had already made him so adept at the art that he was eagerly retained by a Moorish entrepreneur, Francisco Ydrobo, who was delighted to associate himself with a knowledgeable and skillful artisan and so to develop a profitable glassworks. It was remarkable that Juan made no payment to Ydrobo for employing him as an "apprentice," a practice that was usual at the time.
Juan was a clever, ambitious and resourceful young man. When Ydrobo announced that he was going to Fez to obtain business, Juan persuaded Ydrobo to take him along. Juan knew that Fez, in the independent Sultanate of Morocco, was a city in which Jews could openly practice their religion. It was also a city to which Jews flocked to escape the clutches of the Inquisition. Some simply relocated themselves, but others used it to disappear by changing their identity and returning surreptitiously under a new name to Spain through Leghorn, Genoa, or some other port to start life all over again without the surveillance of the Inquisition.
Escape to Fez
Juan and Ydrobo arrived in Fez about 1524. Juan was about 21 years old at the time and was later described by testifiers at his trial before the tribunal of the Inquisition as a dark-skinned, slim young man just beginning to evidence a beard. In Fez, Juan wasted no time in becoming a Jew in fact as well as in spirit. He underwent circumcision and assumed the name "Abraham," a name many proselytes took upon reverting to their faith. He took up residence in the Jewish quarter of Fez.
The tribunal of the Inquisition in Toledo ordered the arrest and trial of Juan Robles, alias Abraham Robles. They called his mother to a hearing and convinced her that it was in Juan's best interest to turn himself in to confess and renounce his heresy. Juan's devoutly Catholic mother, fearing for Juan's eternal damnation, wrote a pleading letter to him, begging him to seek salvation by surrendering.
Juan had a son's deep affection for his mother. He answered, reciting his bitter experience with his "Christian" family, gently denied her request while assuring her of his love.9
"You send to tell me that I have denied you and yours, and I assure you that no such thing could happen, as you know," Juan wrote in compassionate consideration of his mother's feelings. "It is because I could not find any good among your people that I left you. Then I met Ydrobo, and he showed me a goodness such as I have never met from a single one of my relations. They never did anything for me except to use me without pay. There was not even one who was prepared to do the smallest thing that was necessary. I don't owe anything to anyone but Ydrobo, who came here for my sake. And if I live, I will repay him for the losses which he suffered because of me."
Ydrobo also took up residence in the Jewish quarter of Fez. The Judaic community of Fez was always ready to assist proselytes such as Juan to establish themselves, and they extended a helping hand to Juan. Jewish benefactors provided capital to Juan to set up in business, as well as contracts for glassware. Ydrobo garnered orders for glassware from the Moors, and Juan and Ydrobo became partners. Their business flourished.
Ydrobo, however left Juan to sweat at the furnace while he spent most of his time gadding about Fez and tasting its exotic pleasures. Ydrobo's philandering drained the business of its funds, and put it into debt. The partners had a falling out, and Juan set himself up independently.
Ydrobo became bitter and vindictively spread rumors about Juan. These stories reached Juan's mother's ears, and she wrote to him anxiously about them. Juan, now completely disenchanted with Ydrobo, replied:
"When we came here I said to him, ‘Senor, we have no money, but I will borrow 50 ducados and remain here as security. You go to Castilla and get barilla [a soda compound needed for glassmaking] and tools. What did he do, this Ydrobo? He fell in love with a Jewess who lived in the house where he was staying, and he put off his going. Then he came to an agreement with a Moor who gave him the value of his work."
Ydrobo did Juan out of his share. "There is no end to what I can tell you about the things he has done to me in this country." Furthermore, Juan added in his letter, "because he was chasing after this Jewess he didn't work. Only I worked, and he left me to pay for all his losses out of my own money. Not only that. He used to treat me as if I were a Moor. All the Christians here have testified to this. When they tried to intervene, Ydrobo said to them, ‘How do you know that his mother was not my mistress?"
" At the end of it all, by the time I parted with him, I had lost a year and a half of work, and he left me with debts amounting to 22 ducados which I had to pay to the Moors and the Jews for him, because he did not produce anything. He did not even give me money for shoes. He used to tell me that the Moor would give me money. Afterward we became friends, the Moor and I, and he told me that whenever they payed money to Ydrobo, he used to say that I was his servant."
"There is no end to what I can tell you about the things he has done to me in this country. He spent more than 300 ducados on Moorish, Jewish, and Christian women. And most of the money was earned by my work, very little by his."
There was more to the story, for Juan's preparations for changing his identity did not sit well with the authorities. An apprentice under Juan, reported to him that the Sultan was informed about this matter. Juan was certain that it was Ydrobo who did him in. In another letter to his mother he states his fears about this problem, and to his secret preparations to change his identity and furtively gain his way back into Spain.
"[Ydrobo] prevented me from doing what I wanted to do in secret," Juan bitterly recounted, "although nobody [else] would have informed about what I was doing."
It was not merely defamation by Ydrobo that Juan had to contend with. Some Moors accosted Juan and tried to slash his throat. "For no reason, just because they were bad people, against God and man... I feel that I am not going to leave this world without a horrible death. This is a country without justice and without logic, and anyone can come and tell the king any lie at all, and the king believes it."
The city of Fez was rife with intrigue, a city where the conflicting philosophies of Islam, Christianity and Judaism were at odds. At the same time, it was a melting pot of peoples who flowed in through its bustling port from all ends of the Mediterranean. Commerce was its lifeblood and sustained the ostensibly open attitude toward conflicting faiths because the continuation of this lucrative commerce depended on access to all markets. But there was an undercurrent of piracy and double dealing in the conduct of commerce. Additionally, there were the insidious activities of the church to achieve its inquisitorial ends. It could well have been Moorish mercenary gangsters, hired by the monks of the trinity, that threatened the life of Juan.
The Christians were ensconced in a separate compound, as were the Jews. Moorish pirates made a business of abducting Christians and Jews from merchant vessels and holding them for ransom in the Christian compound, an activity the Sultanate ignored. The Christian unfortunates were rescued with money obtained by taxing conversos "for their sins." The conversos thereby "obtained forgiveness."
Monks were employed for delivering the ransoms. These monks also served as Inquisition spies in Morocco, reporting back information gleaned in Fez from informers about former Marranos who had abjured Christianity and had returned to their heritage. Juan, now "Abraham" Robles, was one who had publicly returned to his Judaic faith.
One of the monks who had come to Fez to redeem hostages approached Juan, telling him that he should fear a trial before the forgiving tribunal less than he should fear remaining a practicing Jew in Fez. The monk slyly promised that should Juan return, renounce his heresy, and put himself at the mercy of the tribunal, he would testify in Juan's favor at the trial. The monk informed Juan that judgement was being held in abeyance for his appearance to allow him an opportunity to expurgate himself and thereby earn redemption.
In addition, Juan's mother, under continuous pressure from inquisitorial operatives, ever fearful for her son's soul, continued to exhort Juan to return, begging him again and again to save himself from eternal damnation. Juan was not deceived by the honeyed words of the monk, nor swayed by the apprehension of his mother. He wrote to her, kindly but insistently:
"If we don't manage this carefully, I am going to have a bad end."
Every letter between Juan and his mother was intercepted and scrutinized by the tribunal! Juan had innocently employed as postmen certain merchants who regularly traveled from Spain to Fez to sell hats. Juan entrusted the letters and money for his mother to these hatters because they were ostensibly sympathetic. Juan was oblivious to the fact that the hatters were part of the Inquisition's network of spies and agents. The hatters delivered Juan's correspondence to the tribunal in Toledo where they were copied before they were allowed to pass on.
Unaware of this treachery, Juan wrote guilelessly. He outlined his intentions, stating that as soon as he had satisfied his debts he would change identity and, after passing through through Tunis and Rome, make his way back through Valencia and Aragon. He assured his mother that he then would manage to manoeuver a meeting with her, He was adamant in his refusal to renounce Judaism, but had no intention of laying himself at the mercy of the Inquisition, a mercy he had every reason to distrust, a mercy that included horrendous tortures.
"You say I must return to defend my honor, even to the death. But I don't want to die little by little... I want to die once, not many deaths."
Juan's case was but one of eight heresy cases regarding conversos from the glassmaking community handled by the tribunal. The case of Abraham Robles, the erstwhile Juan Robles was the last one on their agenda. The glassmaking industry of Cadalso, which was "one of the most prolific in Castilla,"10 fell into critical difficulty in 1548 as a result of these proceedings. The inquisitors were acting with rare patience and uncommon restraint in carrying out a verdict on Juan.
"The many adjustments of the case, the many extensions which the court - contrary to its usual practice, gave to the accused to allow him to return, showed how important it was considered by the Inquisition to bring this young man to justice... Perhaps the church authorities were also anxious to stop the break-up of the glassmaking community of Cadalso de los Vidrios."11
Juan's case dragged on for an astounding five years. The first report by a monk returning from Fez to the tribunal on the heresy of Juan Robles, alias "Abraham the heretic," took place in 1530. Almost a year passed before another such returning monk, Pedro de Mata, presented his evidence on Juan at San Martin de Valdeiglesias. This information was transmitted to Toledo, where further investigation was carried out over the period of a year impelled the court to continue prosecution. In 1532 nine witnesses testified to Juan's heresy, yet the tribunal postponed the case by public proclamation on a successive occasions, still seeking to accomplish Juan's return to be tried in person.
The tribunal was about to render judgement when, in January of 1535, Juan's mother, pleaded pitifully before them to allow her yet another opportunity to prevail upon her son to save his soul. She persuaded the now exasperated tribunal to grant her another extension.
Maria Alonso wrote a prayerful, imploring letter to her son, beseeching him to take this last opportunity to exculpate his sins before the bar of the tribunal. Juan's intercepted response was submitted to the magistrates on April 24, 1535. It left no doubt that Juan would never submit to the mercies of the Inquisition, nor renounce his Judaic heritage.
Juan Robles, alias Abraham the proselyte, son of Hernando Robles, glassmaker of Cadalso de los Vidrios, was convicted, burned in effigy, and his soul was condemned to everlasting damnation on December 21, 1535.
Robles' Return to Spain?
That does not appear to be the end of the story to which we are witness. Albeit the tribunal's records end with Juan's conviction as a heretic, there is intriguing evidence that Abraham Robles did secretly re-enter Spain under the alias, "Juan Rodriguez." This "Rodriguez" arrived from Venice to Barcelona, where he practiced the glassmaking art for several years, and then established residence in Seville. Seville had become a thriving crafts center to which artisans thronged. It was also close to a port from which conversos managed to maneuver their way out of Spain, and then through Lisbon, Leghorn and Amsterdam to countries like Brazil, Surinam, Curaçao and elsewhere where they were welcome. Many Marranos had therefore transferred to Seville for such an eventual move, should it become necessary.
"After King Ferdinand II of Castilla reclaimed [Seville and Cordoba] from the Moors (1236-48), their people broke cultural ties with the remaining Islamic kingdoms to the east..., With the beginning of the sixteenth century, a golden age dawned for Sevilla. Wealth and importance, gained through her position as a principal seaport for trade with the Indies, attracted many foreigners to live within her gates. Among them were artists, craftsmen and traders who brought to shops and wharves a beautiful array of treasures - Flemish woven goods and pottery, German and Flemish metalwork and jewels, and the fragile glasses of Venice."12
Among the craftsmen were the glassmaking conversos who carried on their calling in that bustling city. The glassmen of Seville established their furnaces along a street named El Vidrio. Many specialized in making stained glass for the windows of the cathedral, but a few glassblowers produced tableware and ornamental pieces. One of these immigrant glassmakers, named Juan Rodriguez, is recorded in the city's archives as being originally from Cadalso de los Vidrios, from which town he traveled to Venice and Barcelona. This Juan Rodriguez worked in those cities for two years, perfecting his art before coming to Seville, where, in 1557, he applied for permission to set up a furnace. His sponsors, three glassblowers and a merchant, appear likewise to have been Marranos. They testified that, as a master craftsman, Juan Rodriguez knew "how to prepare green glass, latticinio crystal glass of Venetian style, and other favorite varieties."13
All the circumstantial evidence points to the fact that Juan Rodriguez was none other that Juan Robles, who had returned from Fez through Venice and Barcelona under a convenient alias. One sponsor declared that Juan Rodriguez was the son of Hernando Rodriguez of Cadalso Hernando was, of course, the name of Juan's father. There were eleven glassmaking families registered in Cadalso. No Rodriguez glassmaking family was among them!
Rodriquez was of the same age as Robles. The sponsor also stated that Rodriguez had resided in Seville for 20 years. Adding two years for his sojourns in Venice and Barcelona, this adds up to precisely the 22 years between Robles' condemnation in 1535 and 1557, the date of his application for a furnace in Seville.
Juan Robles referred to his sister, Juana, in his letters to his mother. Nothing further appears on the record for a Juana Robles in Cadalso. The sponsor, whose declaration contains the information about the background of Juan "Rodriguez," was a young man named Diego Lopez. Diego's mother's maiden name was registered as Juana Rodriquez!
Juan "Rodriguez" married a Francisca de los Rios, and they had two children, a son named Diego, and a daughter named Juana. Francisca's family, resident in Seville at that time, are likewise recorded as coming from a small glassmaking town near Cadalso de los Vidrios
At that time, the Netherlands were accommodating converso artisans from Portugal and Spain. These immigrants were able to shed their Christian veneer, and resume their life as practicing Jews. The Jewish quarter of Amsterdam became a beehive of Judaic glassmaking activity and they became an important part of the economic life of the city.
Among the glassmaking Marranos who wended their way into Amsterdam were members of the Salas family, a family which had been most distinguished among the glassmakers of Barcelona. It will be remembered that Barcelona was one of the cities in which Juan "Rodriguez" had practiced his trade. The Robles saga appears to have continued on into Amsterdam.
The Amsterdam archival documents record that a Sara Robles is registered as having originated from Seville, and married into the Salas family in Amsterdam in the early 18th century. Sarah was a name commonly taken by converso Jewesses upon returning openly to their faith. Inasmuch as no Robles glassmaking family appears in the census of Seville, and no Rodriguez family existed in Cadalso, it is tempting to surmise that Sara Robles stemmed from Juana Rodriquez, daughter of Juan Rodriguez, alias Abraham Robles, nee Juan Robles!
Refuge in the Carribean
The names Robles and Salas were linked throughout glassmaking history in Italy, Spain, France, and Holland. The Jewish Salas family was the outstanding glassmaking family of Barcelona. After 1492 members of the family dispersed into the Diaspora. A Domenico Sala is recorded to be a Venetian producer of glass in 1572, and a Dominique Sala, and his son, "glassmakers from Catalonia," established themselves in Paris as late as 1906. The families continue to be linked with other erstwhile glassmaking families (de Medina and da Costa) in the records of Surinam, Curacao, and St. Thomas, albeit no longer as glassmakers, for those islands were ill suited for that industry.14
Pedro de Medina, for example, was a glassblower from Burgos, the third important center of glassmaking after Cataluna (Barcelona) and Toledo (Cadalso). Burgos had the largest Judaic communities of Northern Spain, consisting of up to 150 families within the city itself to which must be added other sizable communities of Old and New Castile, each of which hosted from fifty to a hundred families.15 Medina del Campo was among these towns, and was the town from which Pedro stemmed.
During the closing years of the fifteenth century, as we noted above, the Judaic glassmakers were reduced to poverty. They filled menial jobs and lived in the segregated quarters of Medina. In 1490, Pedro de Medina, a converso, "was so badly treated by the owner of a glass factory that he broke away and hired himself to Aluceynt, a Moorish glassblower."15
The records deposited in various communities of the wide Diaspora weave together the history of these and other glassmaking families. A significant list of marriages solemnized by the Dutch-Portuguese Jewish congregation at Surinam from 1642-1750 registers the names of Rachel Robles de Medina, David de Robles, Abigail Robles de Medina, Ester Robles de Medina, Rosa Robles de Medina, Rachel de Robles.16
The descendants of the Judaic glassmakers of Cadalso, Barcelona and Seville are residents of those islands to the present day. An exhibition sponsored by the Israeli museum, the Beth Hatfutsoth, is entitled la Nacion and lists in its catalog those who assisted the exhibition with family records, Prominent among them are the Robles family of Surinam; Mr. Harold Salas of Panama; and Mr. R. Salas of Curaçao. "These descendants of the Marranos..." the catalog states. "came to the region [of the Caribbean] in the 17th century and established a chain of flowering settlements." They termed themselves la nacion.
- The spread of the art of glassmaking by the Jews into the Diaspora is documented in Samuel Kurinsky, The Glassmakers: An Odyssey of the Jews, NY, 1991.
- The letters between Juan Robles and his mother, and the testimony of witnesses supplying other details of Juan Robles' life, are in the Archivio Historico Nacionale, Inquisicion de Toledo, legajo 176 n. 11 folios 22r-22v; 29v-30v; 38r-38v.
- Frothingham, Spanish Glass, London, 1963, 26.
- M. Calmeiro, Historia de la Economia Politica in España, Madrid, 1863, vol. 2, 326.
- Yitzhak Baer, A History of the Jews in Christian Spain, 1961, 122-3.
- Alice Wilson Frothingham, Spanish Glass, 1963, 26.
- Baer, Ibid, 129.
- Baer, Ibid., 365.
Illustration from Hrabanus Maurus, de Universo, Abbey of Monte
Cassino Library, Codex 132.
Heinrich Graetz, History of the Jews, vol. III, ed. Nachum Gross, 1967
The letters from the archives of the Inquisition proceedings in Toledo were published I the original Castiliano by Dr. Haim Beinart, Isaac Zvi Memorial, Jerusalem, 1964. Translated by Father Angel Gonzales; they were published in large measure by Anita Engles, Readings in Glass History, no. 1, Jerusalem, 1973.
- Frothingham, Ibid, 26.
- Anita Engles, Ibid. 76.
- Frothingham, Ibid., 57
- Information cited from the Seville census researches by J. Gestosos y Perez, Ensayo de un diccionario de los artifices que florecieros en Sevilla, Seville, 1900, vol.2, 401.
- P. A. Hilfman, "Notes on the History of the Jews in Surinam," Publication of the American Historical Society no. 18, 1909, 186ff.
- Frothingham, Ibid., 26.
- Anita Engles culled these names from Hilfman, P.A., "Notes on the History of the Jews in Surinam," PAJHS, no. 18, 1909, 186