- Lyndon Baines Johnson (27 August 1908 – 22 January 1973), often referred to by his initials LBJ, was an American politician. After a long career in U.S. legislatures, Johnson became the vice president of the United States of America under John F. Kennedy, from 1961 to 1963. A Democrat, Johnson became the 36th U.S. president in 1963, after Kennedy’s assassination. He served in the role until 1969.