The name was actually given to this type of boot after 1815, when Arthur Wellsley, First Duke of Wellington, defeated Napoleon at Waterloo. This victory made the fellow quite famous and consequently made "Wellington boots" the ultimate fashion. These boots were only calf high, with a low cut. In the ensuing years, especially during the 1850's through 1880's, the full Wellington (two piece, taller than Wellsley's boot) became the standard boot for military officers in America. Americans became very fond of this versatile, horsemen's boot, whereas Europeans still preferred the Wellington's predecessor, the Hessian boot.
Today, Wellingtons are used by a wide crowd of adventurers and sport lovers. You will find steel toe Wellingtons, waterproof rubber Wellingtons, fashionable leather Wellingtons, and countless more styles.