Following the death of King Joao of Portugal in 1494, his son King Manuel I ascended the throne. When his legitimacy as heir to the throne was challenged, Manuel wished to marry Princess Isabel of Spain, daughter of Ferdinand and Isabella, in order to solidify his position. As a precondition to the marriage, the Spanish monarch demanded that Portugal expel its Jews—many of whom were refugees from the 1492 Spanish Expulsion who found refuge in the neighboring country of Portugal. Manuel agreed, and five days after the marriage agreement was signed, on Tevet 23 (5257), he issued a decree giving Portugal’s Jews eleven months to leave the country.
Appreciating the Jews’ economic value, Manuel was unhappy with the potential loss of this economic asset, and devised a way to have the Jews stay in Portugal—but as Christians. Initially, he instructed the Jews to leave from one of three ports, but soon he restricted them to leaving from Lisbon only. When October of 1497 arrived, thousands of Jews assembled there and were forcibly baptized. Many Jews decided to stay and keep their Jewish faith secret; they were called Marranos or Crypto-Jews.
Over the next 350 years, the infamous Inquisition persecuted, tortured and burned at the stake thousands of “marranos” throughout Spain, Portugal and their colonies for continuing to secretly practice the Jewish faith.