In 1941, Sankyū and its parent company Daiki merged to form Kansai Kyuko Railway ("Kankyū"), the precursor to Kintetsu. Before this merger, the Sankyū Main Line had originated at Sakurai and terminated at Ujiyamada, however after the merger the various lines were combined and renamed, resulting in the section between Sakurai and Ise-Nakagawa, along with part of Daiki's lines, becoming the Osaka Line and the section between Ise-Nakagawa and Ujiyamada becoming the Yamada Line, as it is today. In 1944, following mergers with other Kansai area railway companies, Kankyū became Kintetsu and the line came under its current ownership and name. Although the city of Ujiyamada (the basis for the name "Yamada Line") changed its name to Ise in 1955, the train line still maintains the same name to this day.