Zonkaku was a Buddhist priest of Jodo Shinshu (the True Pure Land Sect of Buddhism) who lived from the late Kamakura period to the period of the Northern and Southern Courts (Japan). He was the fourth head of the Kinshoku-ji Temple.
Zonkaku was an outstanding educator in early Jodo Shinshu, and assisting his father, Kakunyo, endeavored to expand the teachings of Jodo Shinshu. But they conflicted over the position of Rusushiki (custodian or caretaker of Shinran's Mausoleum at Otani) of Hongan-ji Temple, the management of the monto (followers) in the eastern Japan and so on, and disownments and reconciliations occurred between them repeatedly two times each. He did not succeed the position of betto (the head priest) of Hongan-ji Temple after reconciliations.
Zonkaku exerted his powers on the activities of edification throughout his life. He transcribed many religious scriptures for Ryogen of Bukko-ji Temple, and did many propagation activities in Kanto, Mutsu Province, Omi Province, Bingo Province and so on.
The following ages are referred to by the traditional Japanese system. The following dates are for consistency with literature written in the old calendar (Senmyo Calendar; except for birth and death dates). The era names for the Northern and Southern Courts are according to the Northern Court (Japan).
In 1297, he became a Yushi (adopted child) of Chikaaki HINO who had once served as Hoki no kuni no kami (Governor of Hoki Province).
In 1303, he studied in Nara at the age of 14, entered into priesthood and received the religious precepts at Todai-ji Temple, and used the name 'Koshin' (興親). He studied under Keikai (慶海), Jitsui (実伊) and Ryokan (良寛) of Kofuku-ji Temple.
In 1309, he studied at Bishamondani-shomonin.
In 1310, he returned from Bishamondani-shomonin to the residence of Kakunyo at Otani, he endeavored to teach disciples by assisting his father.
In 1311, he lectured 'Kyogyoshinsho' to Nyodo (founder of Sanmonto school of Jodo Shinshu) at Omachi Senju-ji Temple in Echizen Province.
This year was the 50th anniversary of Shinran's death.
In 1316, he married Nau.
In 1317, he transcribed Shinran's autographic works, "Kanmuryojukyo Shuchu" and "Amidakyo shicchu".
In 1320, his eldest son 'Koso' (光祖) (the second child, the head of Nanzen-ji Temple in later years) was born.
In 1321, 'Otani-byodo Mausoleum' was converted to a temple and received the name 'Honganji' by Kakunyo. With the conversion into a temple, the position of rusushiki became the position of betto including the position of jujishoku (resident heads of the temples).
In 1322, he was disowned by Kakunyo for the difference of opinions about kechimyaku keisho (Transmission of the Heritage; the secret transmission from the Great Master to only one disciple) of rusushiki and about the monto in the eastern Japan.
In 1324, at Ryogen's request, he wrote "Jodo shin yosho" (Notes on the True Essentials of Pure Land), "Shojin hongaishu" (Collection on the Original Intent of the [Shinto] Kami), "Jimyosho" (Notes on Holding Fast to the Name), and gave them to him.
In the same year, he wrote "Haja Kenshosho" (Notes Assailing Heresy and Revealing Truth) and "Nyoninojo kikigaki".
In 1332, he moved to Okuradani, Kamakura.
In 1334, his fourth son, 'Jikan,' was born (later, he became an adopted heir of Jiku, changed his name to 'Jikan' and the fifth head of Kinshoku-ji Temple).
On December 8, 1335 (old calendar), Ryogen was attacked and killed at Shichiri-toge Pass in Iga Province by villains.
In 1337, he wrote "Kenmyosho" in Bigo Province.
In 1338, he argued with the people of Hokke sect at the provincial government office in Bigo Province. In the same year, he wrote "Kecchi sho," "Hokke mondo," "Hoonki," "Shido sho" and "Senjaku-chugesho" (Commentary on Senjaku).
In 1338, the disownment was remitted by Kakunyo and Zonkaku was reinstated in the position of betto.
In 1342, he was disowned again by Kakunyo.
In 1343, he annotated "Ken jodo shinjitsu kyogyosho monrui" (Selected passages revealing the true teaching, practice and attainment of the Pure Land).
In 1350, the disownment was remitted again by Kakunyo.
In January 19, 1351 (the old calendar), his father, Kakunyo passed away at the age of 82.
In 1353, he moved from the Priest housing in Rokujo Omiya where he had stayed for several years to Imakoji (Kyoto Jorakudai) in Otani and resided there ever since.
In March 22, 1373, he passed away at the age of 84.