Why did the hessians fight?

Answer 1

Because the British bought there help for 150,000$ 30,000 soilders were sent to fight

Hessians were professional soldiers who were often "rented" out to other armies by their rulers, a common practice in 18th century Europe. During the American War of Independence, George III, who had family ties to the Prince of Hess, borrowed and deployed entire regiments of Hessians. Some were volunteers, but many were conscripted, and a few Hessian states kept significant parts of the population under arms. Being a professional princely army, Hessians upheld a strong code of honour. They usually had nothing to gain from the conflict, but fought anyway because it was their duty as soldiers. They served out of a sense of loyalty to their princes and their States.

Answer 2

The Hessians were strongly utilized by the British throughout the 18th century, most notably during the American War of Independence.