The Christianity gained roots in India especially after the Portuguese invasion in ..... in the 16th century.

The spread of Christianity in India is a complex historical process that has been influenced by various factors, including the arrival of European colonial powers. Among these, the Portuguese played a significant role, particularly in the region of Goa. The Portuguese established their presence in Goa in the 16th century, which marked a pivotal period in the history of Christianity in India.

The Portuguese colonization of Goa began in 1510 when Afonso de Albuquerque, a Portuguese general, captured the city from the Bijapur Sultanate. This event marked the beginning of a long period of Portuguese rule in Goa, which lasted until 1961. During this time, Goa became a crucial center for Christian missionary activities in India. The Portuguese were not only interested in establishing a trading post but also in spreading Christianity.

The Portuguese established numerous churches and convents in Goa, which became centers for religious education and conversion. They also brought in missionaries from Europe, who played a significant role in spreading Christianity among the local population. The Portuguese introduced the Latin Rite of the Catholic Church, which became the dominant form of Christianity in Goa. The influence of the Portuguese in Goa was so profound that the region became known as the "Rome of the East."

It is important to note that the spread of Christianity in Goa was not without controversy. The Portuguese used various methods to convert the local population, including offering incentives and sometimes resorting to coercion. This approach led to significant cultural and religious changes in Goa, which are still evident today.

While Christianity spread in other parts of India as well, such as Kerala, the Portuguese colonization of Goa was particularly significant due to the intensity and duration of their presence. The Portuguese influence in Goa was so strong that it shaped the religious landscape of the region for centuries, making Goa a unique case in the history of Christianity in India.

Therefore, the correct answer is Goa, as it was the region where Christianity gained significant roots in India due to the Portuguese invasion in the 16th century.