John II had already, in 1493, seized some two thousand children of Castilian Jewish refugees and shipped them to the newly settled island of São Tomé, where most died. His successor Manuel I decreed the expulsion of Jews and Muslims on 5 December 1496 as a condition of his marriage to a Spanish princess, but did not want to lose the community: he restricted departure to a single port, and in October 1497 had the Jews gathered at Lisbon baptised en masse. Conversion by force created a large New Christian population that was legally Catholic and socially marked, and in April 1506 a Lisbon crowd, incited by friars during plague and famine, killed converts in the streets over roughly three days; the toll is usually given as between one and four thousand and rests on contemporary accounts rather than a count. Emigration was formally barred until 1507 and restricted repeatedly thereafter. The Portuguese Inquisition, established in 1536, pursued the descendants of these forced converts for two centuries.
King Manuel I of Portugal decreed expulsion, then blocked departure and had the Jewish population forcibly baptised; a Lisbon crowd later massacred the converts
Portugal's own Jewish community is generally put at 20,000-30,000 before 1492. Between 20,000 and 60,000 Castilian refugees were admitted in 1492 on payment of an entry tax, giving totals in the sources from about 40,000 to 100,000. The figures derive from Portuguese crown revenue records and contemporary chroniclers, and are contested.
The range is for the Lisbon massacre of April 1506 and comes from contemporary and near-contemporary narratives, including the account attributed to Solomon ibn Verga and reports by foreign residents; there was no official count. Deaths among the children deported to São Tomé in 1493 were reported as very high by contemporaries but were never enumerated.
The seizure of Jewish children for deportation to São Tomé in 1493 and for forced baptism in 1497, and the killing of converts at Lisbon in 1506, are documented in Portuguese royal chronicles, in Jewish narrative sources and in the correspondence of foreign merchants resident in Lisbon.
Portugal, São Tomé and Principe, Netherlands