Also known as Goto Matabei, Mototsugu was the son of Goto Motokuni, chief retainer of the Bessho clan of Harima. When the Bessho's Miki castle was besieged by the Oda and at length forced to surrender in 1580, Motokuni committed suicide. Sometime before, he had given his son into the care of Kuroda Yoshitaka, a retainer of Hashiba (Toyotomi) Hideyoshi who had acted as a messenger in the closing stages of the siege. The young Motostugu grew into a well-known Kuroda warrior; he served in the invasion of Korea and distinguished himself in the Second Siege of Chinju (1593). He went on to fight in the Sekigahara Campaign but left the Kuroda's service some time later. In 1614, for reasons unknown, he joined the defenders of Toyotomi Hideyori at Osaka Castle, perhaps out of a debt he felt for Hideyori's father Hideyoshi, who had spared his life in 1580. Goto fought bravely and well but was killed at the Battle of Domyoji, in 1615, at the tail end of the siege.
Goto was reported to have been a Christian.