In 1510, a Portuguese fleet under Afonso de Albuquerque, sent by King Manuel I of Portugal, wrested the region of Goa from "Sultan" Yusuf Adil Shah of Bijapur. In 1534, the Diocese of Goa was established. Soon missionaries were sent to Goa, which led to conversion of a sizeable population to Roman Catholicism. The bulk of Christian settlers came in three major migration waves towards South Canara. These migrations occurred in periods of great unrest: the Goa Inquisition occurred from 1560 onwards; the Portuguese–Adil Shahi wars were between 1570 and 1579; and the Portuguese–Maratha wars occurred between 1667–83 and 1737–40. Other factors that led to mass migrations were disease epidemics, famines, natural calamities, overpopulation, poor living conditions, heavy tax burdens, and social discrimination by the Portuguese.