Yuri Gagarin did.
40 (his birthday was in July but he orbited the earth in February)
John Glenn orbited the earth, the first American to do so. He was forty at the time.
He wasn't. Yuri Gagarin orbited the earth - once - in 1961, a year before Glenn's flight.
john H. Glenn
John Glenn orbited the earth three times oFebruary 20, 1962 becoming the third American in space and the first American to orbit the Earth.
John Glenn first orbited in Friendship 7, part of the Mercury space program in 1962. He also orbited in the space shuttle in 1998.