The Buddhist Tai-Ahom, led by Sukapha, arrived in Assam in 1228 from what is present day Yunan in China. Befriending the Moran and Borah tribes, and with many of his followers marrying their womenfolk, he is attributed with being the architect of modern Assam. Later, intermixing with immigrant Bengalis, most converted to Hinduism.
The most important Tai-Ahom festival is the Me-Dum-Me-Phi, the ancestor worship festival, which is observed by the whole Tai-Ahom community. An ancient rite dating back some two thousand years, it is performed annually on 31 January. In addition to worshipping ancestors it invokes individuals' life forces to attain social solidarity and vitality in times of peace and conflict, thus helping to develop social contacts and community feeling. It is celebrated with colourful processions and devotees dress up in traditional finery especially for the occasion.
The day begins with the hoisting of the Tai-Ahom flag and is followed by a heralding incantation. Next priests recite incantations in which the whole tribe, old and young, takes part. Children participate in quiz competitions and adults listen to scholars lecturing on the significance of the festival. A community feast is also held at which everyone irrespective of caste, creed, rank or status is welcome.
Due to the increasing participation of many non Tai-Ahom people in this festival it is now celebrated all over Assam.