Masakazu's style came to be called Enshu because he was appointed Totomi no kami (the Governor of Totomi (Enshu) Province) due to his achievement in rebuilding Sunpu Castle in 1608; however, he also gained renown as an architect of buildings and gardens, in which capacity he built and restored buildings around Japan, including the building of the Imperial Palace for Emperor Goyozei, the restoration of Tenshukaku Tower at Nagoya Castle and the reconstruction of Matsuyama Castle in Bicchu Province.
遠州の通り名は慶長13年（1608年）駿府城修築の功績によって遠江守に任ぜられたことによるが、これ以外に後陽成天皇御所造営、名古屋城天守閣の修築、松山城(備中国)の再建など、各地で建物の新造・修繕を務め建築家・造園家として名を馳せた。