Historians have stated that while nothing remarkable took place during Hanzei's brief reign, he did have ranked concubines which is an introduced Chinese custom.

According to the Nihon Shoki, Richū bypassed his own children to make his younger brother Mizuhawake crown prince in 401 AD.

[4] Shortly after his enthronement Hanzei took Tsuno-hime (津野媛) as an "Imperial concubine", and eventually her younger sister Oto-hime (弟媛) as a consort.

[10] During Emperor Hanzei's reign, he ruled from the palace Shibagaki no Miya at Tajihi in the province of Kawachi (present-day Matsubara, Osaka).

[12] Scholar Francis Brinkley lists Emperor Hanzei under "Protohistoric sovereigns", but notes that his short reign was "not remarkable for anything" except for indirect evidence that Chinese customs were beginning to be adopted by the Japanese court.

[c] British academic and Japanologist Basil Hall Chamberlain notes in his translation of the Kojiki that no accurate information exists regarding the ancient Japanese measures used to get Hanzei's alleged height of 9 ft 2.5 in (2.81 m).

[14] His name might have been regularized centuries after the lifetime ascribed to Hanzei, possibly during the time in which legends about the origins of the imperial dynasty were compiled as the chronicles known today as the Kojiki.

[15] While the actual site of Hanzei's grave is not known, this regent is traditionally venerated at a kofun-type Imperial tomb in Sakai, Osaka.

[15] Unless otherwise noted (as BC), years are in CE / AD  * Imperial Consort and Regent Empress Jingū is not traditionally listed.