Yasui Doton (安井道頓)
Doton YASUI (1533 - June 4, 1615) excavated Dotonbori canal. His family name was Yasui-Nariyasu and his common name was Ichiemon. He took the name 'Doton' after undergoing the tonsure.
There are theories that Doton descended from either the Yasui clan or the Nariyasu clan.
Dotonbori Canal
In around 1582, Doton YASUI received the are of Jonan from Hideyoshi TOYOTOMI as a reward for excavating the outer moat of Osaka-jo Castle and for maintaining Nekoma-gawa River bank. In 1612, Doton, believing it necessary to excavate a river in order to develop Jonan obtained permission from the Toyotomi family and began excavating a canal (later known as Dotonbori) in the central area of Jonan at his own expense. During the excavation, he became involved in the Siege of Osaka in 1615 and allied with Hideyori TOYOTOMI's son Hideyori but was killed in Osaka-jo Castle. After Doton's death, Doboku YASUI, Doton's male cousin and Toji HIRANO (Toji ANDO), one of the Sakagami clan of Hirano Ward took over the excavation of the canal with the permission of Tadaaki MATSUDAIRA and completed it in November 1615.
The Nariyasu clan
Doton was said to be the child of Sadatsugu YASUI, but there is also the opinion he was not originally from the Yasui clan but was Doton NARIYASU from the Nariyasu clan of Hirano Ward.
The Nariyasu clan is one of the shichimeike (seven renowned families) of the Hirano clan which descended from SAKANOUE no Hirono, the feudal lord who developed Hirano who was the second son of dainagon (chief councilor of state) and shogun SAKANOUE no Tamuramaro.
In contrast to this theory that he changed from the Nariyasu clan to the Yasui clan is the fact that the Nariyasu clan resided in Hiranogo, Settsu Province whereas Doton is thought to have been born in Kawachi Province, so there is a tendency to deny this theory. However, Hirano-go neighbored Kawachi Province, and the Sakagami and Hirano clans which were families of the Nariyasu clan held territory in Kawachi Province. Therefore, the possibility that Doton NARIYASU was born in Kawachi Province cannot be denied.
Some local historians believe that the Yasui clan lost many families at the time of the attack of Hongan-ji Temple, and that only Sadatsugu survived, which is why he had no encumbrances. There is another theory that since Sadatsugu was not fortunate to have his own child, he adopted a child from the Nariyasu clan, who had power in Hiranogo next to Kyuho-ji Temple in Kawachi Province. Based on historical documentation stating that Doton was Sadatsugu's nephew, some local historians point out that many other possibilities exist, such as the possibility that Sadatsugu's brother was adopted by the Nariyasu clan or that his sister married into the Nariyasu clan. However, Doton's origin has yet to be determined.