- Apr 1 Karl Valentin, Swedish composer, dies at 64
- Apr 5 Paul Vidal de la Blanche, French geographer, dies at 73
- Apr 6 John Q. A. Brackett, American politician, 36th Governor of Massachusetts (1890-91), dies at 75
- Apr 11 Arthur E Ochse, South African cricket batsman (2 Tests; Transvaal), dies in action WWI at 48
- Apr 11 Otto Wagner, Austrian architect and leading figure in the Vienna Secession movement, dies at 76
- Apr 11 William C. McDonald, American lawyer and politician (1st Governor of New Mexico. 1912-17), dies at 59
- Apr 13 Lavr Georgevich Kornilov, Russian military officer, dies at 47
- Apr 20 Karl Ferdinand Braun, German inventor, co-developed wireless telegraphy (Nobel 1909), dies at 67
- Apr 20 Reginald Harry Mybirgh Hands, cricketer (1 Test for SA), dies
The Red Baron (1892-1918)
Apr 21 German World War I fighter ace, dies at 25 after his plane is shot down
- Apr 26 Cecil Coles, Scottish organist and composer (Behind the Lines), killed during WWI by sniper fire while recovering casualties on the Western Front at 29
Gavrilo Princip (1894-1918)
Apr 28 Bosnian-Serb assassin of Archduke Franz Ferdinand, dies of tuberculosis at 23
Assassination
Drug Overdose
Gunshot Wound
Murder
Plane Crash
Suicide