Born in Iida-city, Nagano in 1912, Toshinobu Onosato was brought up in Kiryu-city, Gunma. In 1932, Onosato enrolled in Tsuda Western Painting School directed by Seifu Tsuda, then, got 1st prize at Nika Exibition in 1935. In the same year, he formed avant-garde group “Kokusyoku Youga Ten” (meaning: black colored western painting exhibition). During World War II, he was conscripted into the Japanese Army and the war ended when he was in Manchuria. Then, he experienced three years of detention in Siberia, which had a decisive influence on his style thereafter. In his style after returning to Japan, abstraction evolved all the more letting his unique geometric shapes like circles and lines cover the entire surface of the work. In 1955, he altered the spell of his artist’s name from kanji to katakana which can also be seen as an influence from his minimalistic style. From 1950s, he focused on print making. In 1956, he left “Jiyubijutsu Kyoukai”( Free Artists Association) to which he had belonged from 1938. In 1960s, the accuracy of abstraction further improved repeating exquisite divisions of internal parts of the circles. Onosato was active worldwide including; solo exhibition in Gres Gallery (Washington D.C.) in 1961; 1st prize at the 7th Japan International Art Exhibition; winning Guggenheim Fellowship in 1964; exbibit as one of the artists represented Japan at the 34th Venice Biennale. His unique abstract style bearing optical illusion stood out throughout Japanese Postwar art world. The artist passed away in 1986. In Kiryu, Toshinobu Onosato Museum was built in 1992.