Peter L.W. Osnos was born in Bombay (now Mumbai) India on October 13, 1943. He arrived in Los Angeles by ship with his parents and brother in February 1944. He was raised in New York and attended high school in Connecticut, college at Brandeis University in Waltham, Massachusetts, and graduate school at Columbia University. He worked as an assistant to the journalist I.F. Stone and joined the Washington Post in 1966. At the Post, Osnos served as a correspondent in Vietnam, the Soviet Union, and London. He was also the national and foreign editor. In 1984, Osnos joined Random House as a senior editor and later associate publisher as well as publisher of the Times Books imprint. In 1997, he founded PublicAffairs in partnership with the Perseus Books Group and served as publisher and editor at large until 2020. He was the founder of the Caravan Project on the development of digital and audio publishing, author of a weekly media column called Platform which was hosted by the Century Foundation and appeared on [...] and in 2020, launched Platform Books LLC with his wife, Susan Sherer Osnos.

The first book will be "An Especially Good View: Watching History Happen" to be released in June, 2021. It is Osnos' memoir to be distributed by Two Rivers/Ingram. He is the father of two children, Evan Osnos and Katherine Sanford, and grandfather of five. He and his wife now live in New York City and Lakeside, Michigan.