Many British tacticians outside of the cavalry units realized before the war that advances in technology meant that the era of mounted warfare was coming to an end. However, many senior cavalry officers disagreed, and despite limited usefulness, maintained cavalry regiments at the ready throughout the war. Scarce wartime resources were used to train and maintain cavalry regiments that were rarely used. The continued tactical use of the cavalry charge resulted in the loss of many troops and horses in fruitless attacks against machine guns.

Early in the war, cavalry skirmishes occurred on several fronts, and horse-mounted troops were widely used for reconnaissance.  Britain's cavalry were trained to fight both on foot and mounted, but most other European cavalry still relied on the shock tactic of mounted charges. There were isolated instances of successful shock combat on the Western Front, where cavalry divisions also provided important mobile firepower. Beginning in 1917, cavalry was deployed alongside tanks and aircraft, notably at the Battle of Cambrai, where cavalry was expected to exploit breakthroughs in the lines that the slower tanks could not. This plan never came to fruition due to missed opportunities and the use of machine guns by German forces. At Cambrai, troops from Great Britain, Canada, India and Germany participated in mounted actions. Cavalry was still deployed late in the war, with Allied cavalry troops harassing retreating German forces in 1918 during the Hundred Days Offensive, when horses and tanks continued to be used in the same battles. In comparison to their limited usefulness on the Western Front, "cavalry was literally indispensable" on the Eastern front and in the Middle East.