Namesakes

Bulgarian Presidents and Prime Ministers: 1 prime minister
(prime minister) John Casimir Ehrnrooth   1881  
French Presidents and Prime Ministers: 2 prime ministers
(prime minister) Casimir Pierre Périer   1831-1832  
(prime minister) Édouard Mortier, duc de Trévise (a.k.a. Casimir)   1834-1835  
Olympic Medalists: 1 silver
(silver) Charles Poulenard (a.k.a. Casimir)   1912   4x400 m relay  
Other Royalty: 1 prince
Ernst Casimir of the Netherlands   1822   Netherlands  
Polish High Dukes and Kings: 2 dukes, 2 kings
Duke Kazimierz I the Restorer (a.k.a. Casimir)   1040-1058  
Duke Kazimierz II the Just (a.k.a. Casimir)   1177-1191; 1191-1194  
King Kazimierz III the Great (a.k.a. Casimir)   1333-1370  
King Kazimierz IV (a.k.a. Casimir)   1447-1492  
Saints: 1 saint
Saint Kazimierz of Poland (a.k.a. Casimir)   1458-1484