Why the Portuguese came to India
After the fall of Constantinople to the Turks in 1453, the land route to India was permanently closed. And the Europeans were, so to say, forced to discover the sea route to India. To their good luck, they did find one! An adventurous explorer Vasco da Gama landed in Calicut on 20th May 1498. With this discovery of the sea route to India, a new and glorious chapter of the history of Christianity was opened and the expansion of the Catholic Church in the East began. It marked the introduction of new factors in the field of evangelization in the whole area; they include both new efforts of missionary activity in India, the Moluccas, China and Japan, and the encounter of the western Christianity under the protection and jurisdiction of Padroado, with the ancient Christianity introduced by the St. Thomas Christians in Kerala. In both cases, bright and dark periods accompany the history of Christianity in the following centuries.
The purpose of the Portuguese in coming to India was primarily commercial, of course; they were not directly concerned with conquest; they settled in coastal areas as it was necessary to establish strategic colonies to serve them as trading bases. Goa, with its ideal central position on the west coast was accidentally conquered at the invitation of two Hindus whose intention was to do away with the Muslims from the city of Goa, on the banks of the Mandovi. Goa became the centre of their administration after 1510, while of the series of trading stations they occupied along the coastline, Cochin was the most important. While the merchants were chiefly, if not solely, concerned with commerce, the kings of Portugal were interested in the spread of Christianity as well. So, the merchant fleets brought with them priests who were partly destined to serve the Portuguese as Chaplains, and partly for real mission work. For them too, Goa was the headquarters and it became a diocese in 1534 for the whole Est from Cape of Good Hope to China. In the first years, most of the Chaplains and missionaries were Franciscans. The Jesuits, led by St. Francis Xavier (1542), were later on to be followed by Dominicans (1548), Augustinians (1572), Carmelites (1614) and the Theatines (1640).