Namesakes
Belgian Prime Ministers:
1 prime minister
Étienne Constantin de Gerlache 1831 
German Chancellors and Presidents:
1 chancellor
(chancellor) Constantin Fehrenbach 1920-1921
Notable Artists:
1 sculptor
Constantin Brâncuși 1876-1957
Notable Athletes:
1 soccer
(soccer) Marius Niculae (a.k.a. Constantin) 1981-
Olympic Medalists:
1 gold
(gold) Tobias Hauke (a.k.a. Constantin) 2008; 2012 field hockey
Other Royalty:
3 princes
Constantin of Liechtenstein 1972- Liechtenstein
Georg of Liechtenstein (a.k.a. Constantin) 1999- Liechtenstein
Alfons of Liechtenstein (a.k.a. Constantin) 2001- Liechtenstein
Romanian Presidents and Prime Ministers:
11 prime ministers
(prime minister) Constantin Bosianu 1865
(prime minister) Constantin Crețulescu 1867
(prime minister) Ion C. Brătianu (a.k.a. Constantin) 1876-1881; 1881-1888
(prime minister) Constantin Coandă 1918
(prime minister) Ion I. C. Brătianu (a.k.a. Constantin) 1909-1910; 1914-1918; 1918-1919; 1922-1926; 1927
(prime minister) Vintilă Brătianu (a.k.a. Constantin) 1927-1928
(prime minister) Constantin Argetoianu 1939
(prime minister) Constantin Sănătescu 1944
(prime minister) Constantin Dăscălescu 1982-1989
(prime minister) Mugur Isărescu (a.k.a. Constantin) 1999-2000
(prime minister) Călin Popescu-Tăriceanu (a.k.a. Constantin) 2004-2008