Prince John Konstantinovich of Russia
| Prince John Constantinovich | |
|---|---|
| Born | 5 July 1886 Pavlovsk Palace, Pavlovsk, Saint Petersburg, Russian Empire |
| Died | 18 July 1918 (aged 32) Alapayevsk, Russian SFSR |
| Spouse | |
| Issue | Prince Vsevolod Ivanovich Princess Catherine Ivanovna |
| House | Holstein-Gottorp-Romanov |
| Father | Grand Duke Constantine Constantinovich of Russia |
| Mother | Princess Elisabeth of Saxe-Altenburg |
Prince John Konstantonovich of Russia, born as Grand Duke John Konstantinovich of Russia (Russian: Иоанн Константинович; 5 July 1886 – 18 July 1918), sometimes also known as Prince Ivan, Prince Ioann or Prince Johan, was the eldest son of Grand Duke Konstantin Konstantinovich of Russia by his wife, Yelizaveta Mavrikievna, née Princess Elisabeth of Saxe-Altenburg. He was described by contemporaries as a gentle, religious person, nicknamed "Ioannchik" by his relatives.