How many Hessian mercenaries fought for Britain in the American Revolution?

During the American Revolution, the British government hired approximately 30,000 troops from various German princes to supplement their professional army. Of this total, the landgrave of Hesse provided approximately three-fifths, which amounts to roughly 18,000 soldiers. These forces were commonly referred to as Hessian mercenaries, and their employment by the British crown was a significant source of antagonism among the American colonists.12