仁徳天皇
In the Japanese archipelago, there are tumuli (kofuns), which are mounds of earth and stones erected over graves of the ruling class. More than 20,000 were built as monuments between the later part of the 3rd century and the 6th century. It was the peak period of building such mounds. They represent a cultural tradition which is an expression of "forms, and design of the kofun" of the sociopolitical hierarchical order and the link that was prevalent during that period between regions. This period is termed as the Kofun Period. The most prominent imperial mausolea in this cluster of tumulus are those of Emperor Nintoku and Emperor Richū.