Namesakes
Estonian Presidents and Prime Ministers:
1 president
(president) Arnold Rüütel 2001-2006 
Fictional Characters from Song Titles:
1 character
(character) Arnold Layne 1967 Arnold Layne
Fictional Characters from Television:
1 character
Arnold Shortman 1996 Hey Arnold!
Hall-of-Famers:
2 football, 1 basketball
(football) Arnie Herber 1966
(football) Arnie Weinmeister 1984
(basketball) Arnie Risen 1998
Nobel Prize Winners:
1 peace
(peace) Al Gore (middle name Arnold) 2007
Notable Actors and Entertainers:
4 actors
Mario Lanza (middle name Arnold) 1921-1959
Arnold Schwarzenegger 1947-
Rodney A. Grant (middle name Arnold) 1959-
Arnold Vosloo 1962-
Notable Artists:
1 painter, 1 photographer
Arnold Böcklin 1827-1901
Arnold Genthe 1869-1942
Notable Athletes:
2 soccer, 1 basketball, 1 golf, 1 ice hockey, 1 skating
(skating) Clas Thunberg (a.k.a. Arnold) 1893-1973
(ice hockey) Rune Johansson (middle name Arnold) 1920-1998
(basketball) Arnie Risen 1924-2012
(golf) Arnold Palmer 1929-2016
(soccer) Arnold Mühren 1951-
(soccer) Steven Defour (middle name Arnold) 1988-
Notable Musicians:
2 composers, 1 musician/singer
Arnold Schoenberg 1874-1951
Peter Warlock (middle name Arnold) 1894-1930
Waylon Jennings (middle name Arnold) 1937-2002
Notable Philosophers and Thinkers:
1 historian
Arnold J. Toynbee 1889-1975
Notable Politicians and Statespeople:
1 politician
Al Gore (middle name Arnold) 1948-
Notable Scientists and Inventors:
1 physicist
Arnold Sommerfeld 1868-1951
Olympic Medalists:
1 bronze, 1 bronze/silver/gold, 1 gold, 1 gold/silver/bronze, 1 silver
(gold) Arnold Jackson 1912 1500 m
(bronze/silver/gold) Clas Thunberg (a.k.a. Arnold) 1924; 1928 speed skating
(silver) Maxwell Deacon (middle name Arnold) 1936 ice hockey
(bronze) Arnold Vanderlyde 1984; 1988; 1992 boxing
(gold/silver/bronze) Bronte Barratt (middle name Arnold) 2008; 2012 swimming
Saints:
4 saints
Saint Arnold ?-800
Saint Arnold of Soissons 1040-1087
Saint Arnold of Selenhofen 1095-1160
Saint Arnold Janssen 1837-1909
Swiss Presidents:
1 president
Arnold Koller 1990; 1997