For about 3,000 years, one of the scariest sights on any battlefield was a wall of armored soldiers thundering toward you on horses. Cavalry first appeared in ancient times and stayed in use right up until the early 1900s. Mongol horse archers, medieval knights and Napoleonic dragoons all built their tactics around how fast and powerful a charging horse could be.
The first true tank rolled onto a battlefield in 1916 during World War I. Early tanks were slow, clunky and often broke down - but they could crash through barbed wire and shrug off machine-gun bullets, which cavalry simply couldn’t. Each new generation of tanks got faster, tougher and more deadly.
Even so, horses weren’t gone overnight. In World War II, both German and Soviet armies still used hundreds of thousands of horses to pull wagons and artillery. The last big cavalry charge in modern history happened in 1939 when a Polish cavalry unit fought German troops with sabers in the early days of the war.
