Namesakes
Finnish Presidents and Prime Ministers:
1 president, 1 prime minister
(prime minister) Kaarlo Castrén 1919 
(president) Kaarlo Juho Ståhlberg 1919-1925
Olympic Medalists:
1 bronze, 1 silver, 1 silver/bronze
(silver) Kaarlo Tuominen 1936 3000 m steeplechase
(bronze) Kalervo Toivonen (a.k.a. Kaarlo) 1936 javelin throw
(silver/bronze) Kaarlo Maaninka 1980 10000 m; 5000 m