Samuel de Champlain, an early French explorer of North America, was the first European to discover the Green Mountains. In the summer of 1609, Champlain left his encampment on the St. Lawrence in Quebec and joined the Algonquians in an expedition against their enemies, the Iroquois. The journey up the river brought Champlain onto the lake that now carries his name on July 4, 1609.

The name "Vermont" is itself derived from the French, les monts verts, "the green mountains."

The first permanent English settlement was established along the Connecticut River in 1724 at Fort Dummer, near what is now Brattleboro. The fort was maintained by the colonial governments of Massachusetts and New Hampshire as a defensive outpost throughout the French and Indian Wars.

When peace was made with the French in 1760, the Green Mountains were quickly opened to settlement, and to considerable squabbling between the colonies of New Hampshire and New York as to which had the proper claim to the territory, then called the New Hampshire Grants. Most of the new settlers were from Connecticut or Massachusetts and persistently resisted the claims of authority by New York. Resistance to the "Yorkers" brought the organization of the Green Mountain Boys under the leadership of Col. Ethan Allen in 1775; this small but experienced army came to play a significant role during the American Revolution at the battles of Hubbardton and Bennington in 1777.

On January 17, 1777, Vermont was declared an independent republic in a meeting held at Westminster. This independent course, with the little republic minting its own coin and providing postal service, was followed until 1791 when Vermont was admitted to the union, the first state to join the original thirteen. The first governor was Thomas Chittenden.