Was Christianity present in India before the arrival of Europeans?

Since the other answer has been removed, the answer is yes. Here is me quoting myself from an earlier thread on a related question:

In the case of India, the tradition contained in the Acts of Thomas suggests that Thomas went to India. While difficult to put much historical reliance upon it, the text itself suggests that the tradition that Thomas went to India dates at least to the 3rd century. To be fair, it is not impossible that Thomas went to India, just very difficult to verify. The document discusses a King Gundaphar, who appears to be a verified figure from the 1st century. Anyway, whether Thomas got there or not is pretty difficult to establish. A second mission is recorded, in that Pantaenus, a scholar from Alexandria, was sent from Alexandria around 179/180 AD. The account recorded in Eusebius suggests both that Christians were already there, and they had the Gospel according to Matthew in their language, thanks to the apostle Bartholomew.

Anyway, the Syrian church is very well attested throughout the Late Antique period, and records missionaries travelling from Edessa eastward, to the borders of Mesopotamia and beyond. One has to wait until the later fourth century for a number of references in sources to Christians in India, and from the early 5th century you begin to get details about Indian Christians being organised at a hierarchical level into the Persian church structure.

S.H. Moffett’s “A History of Christianity in Asia” is a good starting place for this kind of thing.

The Thomistic churches, obviously, carry a traditional interpretation that they were founded by Thomas the apostle. Even if this is not taken at face value, the evidence suggests Christianity arrived in India pretty early, and for the most part independent of the church in the Roman Empire. 'European' contact, if you define it by the sea voyage of Vasco de Gama in 1497-99 is much, much later.