March 4, 1791 – Vermont is admitted to the U.S. as the fourteenth state.

Vermont (i/vɜrˈmɑːnt/,[5] [vɚːˈmɑːn(ʔ ] or [vɚˈmɑ̃ ʔ ][6]) is a state in the New England region of the northeastern United States. Vermont is the 6th least extensive and the 2nd least populous of the 50 United States. It is the only New England state not bordering the Atlantic Ocean. Lake Champlain forms half of Vermont's western border, which it shares with the state of New York. The Green Mountains are within the state. Vermont is bordered by Massachusetts to the south, New Hampshire to the east, New York to the west, and the Canadian province of Quebec to the north.

Originally inhabited by two major Native American tribes (the Algonquian-speaking Abenaki and the Iroquois), much of the territory that is now Vermont was claimed by France during its early colonial period. France ceded the territory to the Kingdom of Great Britain after being defeated in 1763 in the Seven Years' War (also called the French and Indian War). For many years, the nearby colonies, especially New Hampshire and New York, disputed control of the area (then called the New Hampshire Grants). Settlers who held land titles granted by these colonies were opposed by the Green Mountain Boys militia, which eventually prevailed in creating an independent state, the Vermont Republic. Founded in 1777 during the Revolutionary War, the republic lasted for fourteen years. Setting aside the Thirteen Colonies, Vermont is one of only five U.S. states (along with Texas, Hawaii, California, and the briefly declared Republic of West Florida) to have been a sovereign state in its past. In 1791, Vermont joined the United States as the 14th state, the first outside the original 13 Colonies. It abolished slavery while still independent, and upon joining the Union became the first state to have done so.

http://en.wikipedia.org/wiki/Vermont