, also known as 稚足彦天皇, was the 13th legendary Emperor of Japan, according to the traditional order of succession. Both the Kojiki, and the Nihon Shoki (collectively known as the Kiki) record events that took place during Seimu's alleged lifetime. This legendary Emperor is best known for organizing his local governments by making the first appointments of their kind to provinces under his rule. Seimu had only one recorded wife who bore him a single child; he also had a concubine but she had no children. This is in stark contrast to his father, who is said to have had at least 80 children with multiple wives.
Seimu's reign is conventionally considered to have been from 131 to 190 AD. An issue ultimately occurred when his only son allegedly died at a young age. Seimu appointed one of his nephews to be crown prince before his death in 190 AD, marking the first of later generations which would cede the throne to a non-direct successor. While the location of Seimu's grave (if any) is unknow