 Niwa Nagahide became a senior retainer of Oda Nobunaga and after Nobunaga was assassinated at the Honnō-ji Incident, helped Toyotomi Hideyoshi defeat the forces of Akechi Mitsuhide at the Battle of Yamazaki.He also assisted Hideyoshi at the Battle of Shizugatake, and was rewarded with the provinces of Wakasa and Echizen and two districts of Kaga Province, for a total "kokudaka" of 1,230,000 "koku", making him one of the most powerful Sengoku-"daimyō".However, after Niwa Nagahide died in 1585, the clan's fortunes under Niwa Nagashige fell with equal rapidity.