As a counterpoint to European developments in the strategic art, the Mongol Emperor Genghis Khan provides a useful example. Genghis' successes, and those of his successors, were based on manoeuvre and terror. The main focus of Genghis' strategic assault was the psychology of the opposing population. By steady and meticulous implementation of this strategy, Genghis and his descendants were able to conquer most of Eurasia. The building blocks of Genghis' army and his strategy were his tribal levies of mounted archers, scorched earth-style methods, and, equally essential, the vast horse-herds of Mongolia.