Some of these are surprising
1: Morgan Freeman – Air Force, 1955-1959
2: Bea Arthur, Marine Corps Women’s Reserve, 1943-1945
3: Elvis Presley, Army, 1958-1960
4: Bob Ross, Air Force, 1961-1981
5: Chuck Norris, Air Force, 1958-1962
6: Bill Cosby, Navy, 1956-1960
7: Dan Rather, Marine Corps, 1954, he was discharged just after enlistment
8: Drew Carey, Marine Corps Reserve, 1981-1987
9: Ed McMahon, Marine Corps, 1941-1966
10: George Carlin, Air Force, 1954-1957
11: Hugh Hefner, Army, 1944-1946
12: Jackie Robinson, Army, 1942-1944
13: Maynard James Keenan, Army, 1982-1984
14: Al Gore, Army, 1969-1971
15: Jimi Hendrix, Army, 1961-1962
16: Jimmy Stewart, U.S. Army Air Force, 1941-1968
17: John Coltrane, Navy, 1945-1946
18: Kris Kristofferson, Army, 1960-1965
19: Kurt Vonnegut, Army, 1943-1945
20: Leonard Nimoy, Army Reserve, 1953-1955
21: Mel Brooks, Army, 1944-1946
22: Montel Williams, Marine Corps and Navy, 1974-1980
23: Johnny Cash, Air Force, 1950-1954
24: Paul Newman, Navy, 1943-1946
25: Rob Riggle, Marine Corps Reserve, 1990-2013
26: Shaggy, Marine Corps, 1988-1992
27: Tom Selleck, Army National Guard, 1967-1973
Source: Imgur