On Twitter, the actor promised that it's going to be grand:
Need ur best wishes for Sons Of Sardaar, will match the scale of Hollywood war film 300 and based on epic Battle of Saragarhi. Diwali 2017Ajay Devgn (@ajaydevgn) August 19, 2015
Sons of Sardaar sounds like a sequel to the 2012 film Son of Sardaar that Ajay produced and starred in, but the only thing the two films will have in common is the similarity of name. Unlike the original action comedy, Sons of Sardaar will be based on a page from the history books and will tell the story of the 21 Sikhs who fought to death in the 1897 Battle of Saragarhi.
On September 12, 1897, a 21-strong contingent from what is now the Sikh Regiment defended an army post in the North West Frontier Province against 10,000 Afghan tribesmen. All 21 Sikh soldiers fought to death, shouting the battle cry of "Jo Bole So Nihal, Sat Sri Akal." They posthumously received the Indian Order of Merit, which was British India's equivalent of the Param Vir Chakra and Saragarhi Day is celebrated every September 12 in Sikh communities around the world.
Details about the planned film are yet unknown. Ajay Devgn already has experience with historical subjects, having won a National Award for his performance as the titular freedom fighter in 2002's The Legend of Bhagat Singh.