Tato is situated in the Shi-Yomi district of Arunachal Pradesh. Tato is inhabited by the Pailibo, a sub tribe of Adi, which is one of the major tribes of Arunachal Pradesh. Till 1995, there was no road communication to this area. But some of the daring children from these inaccessible areas went to Assam and other places for study. Many were staying in the hostels run by fathers and sisters. In the year 1993, Fr. LukoseKavunkal from Silapathar came for the first time to Tato and initiated some contacts. In the year 2002, Fr. Thomas Kollathuvayalil and Fr Mathew Vazheparambil started to reside there and it was declared as a parish.

Missionary Sisters of Mary Help of Christians (MSMHC)

Considering the distance and location of Tato, it was a daring step from the part of Missionary Sisters of Mary Help of Christians of Tezpur Province to start a community at Tato on May 24, 2006. The pioneers were Srs Milani Guria and AgenciaTopo. Now there are four nuns working in the parish regularly, engaging fully in all its activities. They work closely with the fathers in visiting the villages and families, in the hostel and the school. In the beginning they ran a dispensary but had to give up the service due to practical reasons.