Aso Koretoyo (阿蘇惟豊)
Koretoyo ASO (1493 - December 5, 1559) was the eighteenth family head of the Aso clan in the Sengoku Period (the high priest of Aso-jinja shrine). He was a child of Korenori ASO. He was the father of Koremasa ASO and Koretane ASO. He was assisted by Chikanobu KAI and his son Chikanao KAI (Soun) and built the golden age of the Aso clan. He was one of the people of five offices in Aso. His official rank was Junii (Junior Second Rank), the high priest of Aso-jinja shrine.
In 1505, he became the family head by taking over as the head of the family from his older brother Korenaga ASO (Taketsune KIKUCHI) who seized the Kikuchi family of Higo no kuni Shugo (Provincial Constable of Higo Province). However, in 1513, he was attacked by Korenaga who plotted to return to the family head of the Aso clan, then he escaped to Hyuga Province. He received support from Chikanobu KAI, kokujin (local samurai) of Takachiho Kuraoka, and in 1517 he recaptured Yabe, the base of the Aso clan. After that, he still had a struggle against Korenaga and his son Koresaki ASO, and in 1543 he captured Katashida-jo Castle and put Koresaki to rout and practically put an end to a division among the Aso clan over thirty years.
In 1549, he dedicated 10,000 hiki (110,000,000 yen) as charges for repairing the Imperial Palace to the Imperial Court and he was conferred Junii (Junior Second Rank) by the Emperor Gonara. In 1540, he was said to receive 'Hannya Shingyo' (Heart Sutra) that was in the Emperor Gonara's own writing and devote it to Aso jogu (building of a Shinto shrine complex built upon the highest ground of Aso-jinja shrine).