Kluck saw service in the Seven Weeks' War (1866) and in the Franco-German War (1870–71). In 1906 he became a general of infantry and in 1913 an inspector general. On the outbreak of war in 1914 he assumed his war appointment as commander of the 1st Army on the extreme right flank of the German force that would penetrate into northern France. His task was to roll up the left flank of the French armies, encircle Paris, and thus bring the war in the West to a rapid conclusion. These plans miscarried, partly because of lack of control by supreme headquarters, with Kluck's army prematurely executing a wheel to the west of Paris, a maneuver that opened up a gap in the German lines which afforded an opportunity for a counteroffensive by French and British forces. Kluck almost succeeded in reaching Paris but was defeated only 13 miles from the city by Anglo-French forces in the First Battle of the Marne (Marne, First Battle of the), Sept. 6–9, 1914. By October 1914 the German advance had been halted and trench warfare had begun.

Kluck was wounded in March 1915 and retired the next year. His version of the battle, which lost him his command, can be found in his book Der Marsch auf Paris und die Marneschlacht (“The March on Paris and the Battle of the Marne”; 1920; 2nd ed., 1926).