Voltaire came to London in May 1726 and stayed here until October or early November 1728. During that time he became involved, in very curious circumstances, with the Mendes da Costa family.
The Mendes da Costas were among the first Sephardi merchants then resident in Portugal or Amsterdam to come over to England after the famous decision by legal experts in 1655 that there was no law in force prohibiting Jewish re-entry into the kingdom. This converso family had lived in Trancoso in Beira Alta, well to the northeast of Lisbon, from at least the end of the sixteenth century.((Many of the following details come from the enormous and detailed genealogical table established by Mr A. Mendes da Costa of New Zealand and kindly shown and elucidated to me by Mr Edgar Samuel. I have been able to correct, or add to, this table by research at the Public Record Office (PRO), and elsewhere, but some details remain undocumented. The com? ments are my own.)) Luis Henriques da Costa (bora in 1585) and his wife Leonor Mendes Gutierres had seven children between the years 1608 and 1623 (Table I).
The family was clearly prosperous and well respected: one of Luis' sons, Jorge, is said to have been Clerk of the Court of Trancoso at some stage, before he had to take flight from possible persecution, probably in the 1650s.
At least two of the sons of Luis and Leonor, together with their wives, were suspected of judaizing and attracted the unwelcome attentions of the Holy Office. Recent enquiries by Mr Edgar Samuel, for which I am extremely grateful, have produced from the Portuguese National Archives (Arquivo Nacional da Torre do Tombo) copies of entries in the Inquisitorial records concerning these members of the family. These provide several important facts. One son of Luis, Joao Mendes da Costa, figures on the Lista (programme) of the Coimbra auto de fe of 27 August 1663, and his wife Maria Soares on the Lista of another Coimbra auto of 31 January 1665. These are recorded in the Livro dos homens (Inq. Lisboa, fl.423). Whether they were condemned, and what punishment, if any, they received, is not in the records made available to me, but they must eventually have been released from custody since they are later known to have made their way with numerous children to Bayonne, where Jo?o apparently died in 1675. (Jorge, incidentally, seems to have headed for London but eventually settled in Antwerp; Felipe also settled in London; but their two sisters have left no trace.) The other two brothers, Fern?o and Antonio, also emigrated and founded between them the London dynasty of Mendes, da Costa and Mendes da Costa: these are the two who in time provided through their progeny the contact with Voltaire.
Fern?o (Table II) is the other son of Luis and Leonor, who, with his wife, was suspected of judaizing. The brief dossier on him in the Livro dos homens (Inq. Lisboa,