When World War I began in August 1914, the three ships in French waters were assigned to defend Allied shipping in the English Channel and enforce the blockade of Germany while "Condé" was tasked to hunt down German commerce raiders in the Western Atlantic. Once the defenses of the Channel were completed in 1915, the sisters spent most of the rest of the war patrolling the Atlantic or on convoy escort duties based in either France or the West Indies. "Amiral Aube" was sent to the Eastern Mediterranean in late 1915 where she patrolled off the coast of Ottoman-controlled territory, but returned to France in early 1916. The ship was sent to Murmansk in early 1918 to support Allied forces when they intervened in the Russian Civil War. Returning home in October, she joined her sisters in the Atlantic Division (), based in the West Indies, in early 1919.