Mark Lewisohn was born in London in 1958. He is widely considered the world s leading historian and authority on The Beatles, a reputation that began in his years as a researcher for other writers and was confirmed in 1986 when he authored The Beatles Live! a diary-like account of the group as stage performers. Since then he has written several further books on the group, including Recording Sessions and the New York Times bestselling Tune In, the first volume in his independent biographical history The Beatles: All These Years. He is presently at work on volume two.