Born in Fukushima City, Japan, Osada graduated from Waseda University in 1963. He made his literary debut in 1965 with the poetry collection This Journey. In 1971, he traveled to the United States as a member of the International Creative Writing Program at the University of Iowa.[1]
Known outside of Japan for his children's books, it was Osada's poetry that garnered him recognition in his native Japan.[1] In 1982, he was awarded the Mainichi Publishing Culture Award for his book The Bookstore of the Century. In 1991, he received the Robō-no-ishi Literary Prize for The Making of Memories.[2]
Osada's collaboration with illustrator Ryōji Arai on A Forest Picture Book, won the Kōdansha Publishing Culture Award for Children's Literature in 2000. The duo continued their partnership with the publication of Every Color of Light, which was later translated to English by David Boyd, subsequently winning awards for best book (Kirkus Reviews) and best picture book (Publishers Weekly).[3][4]