Christianity in India is the third-largest religion in that nation, following Hinduism and Islam. Abrahamic religions on the whole date back about 2500 years with the arrival of Judaism, followed by arrival of Christianity around 2000 years ago. Christianity came to India very early, several centuries before it reached parts of Europe.
Christianity came to India in two main periods, the first century missionary activity of Thomas, the disciple of Jesus, and the Western missionary activities from 1500 to 1975. Vasco da Gama, seeking pre-existing Christian nations in India, discovered a sea route to India by circumnavigating the Cape of Good Hope which caused a major influence on both the histories of Asia and Europe.
The total official number of Christians in India as per Census in 2001 are 24,080,016 or 2.34% of the population. It is the estimated that the number of crypto Christians (Hindus who have been converted to Christianity but continue to officially register themselves as Hindus to claim government benefits could be as high as 70 million. Number of such crypto Christians abound amongst the Dalit community in India where large number of evangelistic and conversion activities are being carried. This would take the actual number of Christians in India to nearly 100 million or ~ 10% of Indian population.
There are three main regional concentrations of Christian population, namely in South India, on the Konkan Coast, and among tribal people in East, Central, and North-East India. The states of Kerala and Tamil Nadu in South India and Arunachal Pradesh in North-East India account for 60% of India's total Christian population.
Orrisa and Andhra are significant frontiers of Church activity with a goal to convert 50% population in Orrisa by 2010. Recent events have included Church using Maoist terrorists to gun down Swami Lakshmanand Saraswati, a 84 year old Hindu monk working to reconvert Hindus.