Josephine Jacobsen was born in Cobourg, Canada. She moved with her family to the USA as a young teenager, settling in Maryland. She graduated from the Roland Park Country School in Baltimore in 1926.
She published numerous collections of poetry, including In the Crevice of Time (1995), The Chinese Insomniacs (1981), The Shade-Seller (1974), and The Animal Inside (1966), and also wrote short fiction and literary criticism.
She served as Poetry Laureate Consultant to the Library of Congress from 1971-1973, and as Honorary Consultant in American Letters to the Library from 1973-1979. She was a vice president of the Poetry Society of America and a member of the literature panels of the National Endowment of the Arts and the poetry committee of Folger Library.
She was elected to the American Academy of Arts and Letters in 1994.