Hola Mohalla is a Sikh festival that takes place on the first of the lunar month of Chet, which usually falls in March. This, by a tradition established by Guru Gobind Singh, follows the Hindu festival of Holi by one day; Hola is the masculine form of the feminine sounding Holi. The word “Mohalla” is derived from the Arabic root hal (alighting, descending) and is a Punjabi word that implies an organized procession in the form of an army column.
But unlike Holi, when people playfully sprinkle color, dry or mixed in water, on each other, the Guru made Hola Mohalla an occasion for the Sikhs to demonstrate their martial skills in simulated battles.
Together the words “Hola Mohalla” stand for “mock fight.” During this festival, processions are organized in the form of army type columns accompanied by war-drums and standard-bearers, proceeding to a given spot or moving in state from one Gurdwara to another.
The custom originated in the time of Guru Gobind Singh, who held the first such mock fight event at Anandpur Sahib in February 1701. The foothills of the Shivaliks in Ropar district of Punjab’s north-eastern region, especially around the historic townships of Anandpur Sahib and Kiratpur Sahib, have, since 1701 been playing host to Hola Mohalla.
The military exercise, which was personally supervised by the Guru, was carried out on the bed of the River Charan Ganga with the famous Hindu temple of Mata Naina Devi in the Shivaliks as the backdrop.
The Indian government eventually accorded it the status of a national festival.
Sourced from https://www.sikhdharma.org/the-sikh-festival-of-hola-mohalla