After four decades of prosperous trading, the missionaries started the proselytisation around 1540 and during this period, foreign missionaries also made many new converts to Christianity. Early Roman Catholic missionaries, particularly the Portuguese, led by the Jesuit St Francis Xavier (1506–1552), expanded from their bases on the west coast making many converts. The Portuguese colonial government supported the mission. At the same time many New Christians from Portugal migrated to India as a result of the inquisition in Portugal. Many of them were suspected of being Crypto-Jews, converted Jews who were secretly practising their old religion. Both were considered a threat to the solidarity of Christian belief, which is considered a blot on the history of Roman Catholic Christianity in India, both by Christians and non-Christians alike.