Dota Masahisa was a bushi, or local warrior. He held the title of Governor of Shimōsa. Masahisa was the son of Dota Hidehisa. His mother was the daughter of Ikoma Iehiro. Under one theory, he may be the same individual as Ikoma Chikashige. He was the father of Dota Gozen, the natural mother of Oda Nobunaga.
The Dota clan is affiliated with one of two influential families: The Dota from the Kani District of Mino Province or the Tsuchida from the Kaitō District of Owari Province. The Dota have origins in Ōmi Province, and were a branch of the Yamauchi family who served the Rokkaku clan.
Hidehisa wed the daughter of Ikoma Iehiro, a wealthy family from the Kōri District of Owari, but after separating he returned the daughter to her family home. However, she was already pregnant with their second child, believed to be Masahisa. Masahisa served Oda Nobuyasu for a long time, and had his son, Ikoma Chikashige married the daughter of Ikoma Toyomasa (Iehiro’s son) and resided with them.
Toyomasa had a son named Ikoma Iemune. Iemune’s daughter married Dota Yaheiji of Mino Province, but returned to her family home after his death in battle.