York County, Massachusetts was a county in what is now the U.S. state of Maine

Maine

Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...

. It was established in 1652 when the Massachusetts Bay Colony

Massachusetts Bay Colony

The Massachusetts Bay Colony was an English settlement on the east coast of North America in the 17th century, in New England, situated around the present-day cities of Salem and Boston. The territory administered by the colony included much of present-day central New England, including portions...

 first asserted territorial claims over the settlements of southern Maine, extending from the Piscataqua River

Piscataqua River

The Piscataqua River, in the northeastern United States, is a long tidal estuary formed by the confluence of the Salmon Falls and Cocheco rivers...

 to just east of the mouth of the Presumpscot River

Presumpscot River

The Presumpscot River is a river located in Cumberland County, Maine. It is the main outlet of Sebago Lake.-Course:The river flows through the communities of Standish, Windham, Gorham, Westbrook, Portland, and Falmouth before emptying into Casco Bay at Falmouth...

 in Casco Bay

Casco Bay

Casco Bay is an inlet of the Gulf of Maine on the southern coast of Maine, New England, United States. Its easternmost approach is Cape Small and its westernmost approach is Two Lights in Cape Elizabeth...

. The county eventually grew to encompass effectively all of present-day Maine, although the interior was claimed by various Abenaki peoples, and the territory east of Penobscot Bay

Penobscot Bay

Penobscot Bay originates from the mouth of Maine's Penobscot River. There are many islands in this bay, and on them, some of the country's most well-known summer colonies. The bay served as portal for the one time "lumber capital of the world," namely; the city of Bangor...

 was claimed (and partly occupied) as part of French Acadia

Acadia

Acadia was the name given to lands in a portion of the French colonial empire of New France, in northeastern North America that included parts of eastern Quebec, the Maritime provinces, and modern-day Maine. At the end of the 16th century, France claimed territory stretching as far south as...

. By 1760 most of the Abenaki had either been wiped out or retreated northward toward the Saint Lawrence River

Saint Lawrence River

The Saint Lawrence is a large river flowing approximately from southwest to northeast in the middle latitudes of North America, connecting the Great Lakes with the Atlantic Ocean. It is the primary drainage conveyor of the Great Lakes Basin...

, and New France

New France

New France was the area colonized by France in North America during a period beginning with the exploration of the Saint Lawrence River by Jacques Cartier in 1534 and ending with the cession of New France to Spain and Great Britain in 1763...

 had been conquered in the French and Indian War

French and Indian War

The French and Indian War is the common American name for the war between Great Britain and France in North America from 1754 to 1763. In 1756, the war erupted into the world-wide conflict known as the Seven Years' War and thus came to be regarded as the North American theater of that war...

.

The large size of the county led to its division in 1760, with Cumberland

Cumberland County, Maine

Cumberland County is a county located in the U.S. state of Maine. As of 2010, the population was 281,674. Its county seat is Portland, and is the most populous of the sixteen Maine counties, as well as the most affluent. Cumberland County has the deepest and second largest body of water in the...

 and Lincoln

Lincoln County, Maine

Lincoln County is a county located in the U.S. state of Maine. As of 2010, the population was 34,457. Its county seat is Wiscasset. It was founded in 1760 and named after the English city Lincoln. At its founding, it accounted for three-fifths of the State's land, and stretched east to Nova...

 counties carved out of its eastern portions. When Massachusetts adopted its state government in 1780, it created the District of Maine

District of Maine

The District of Maine was a legal designation for what is now the U.S. state of Maine from American independence until the Missouri Compromise on March 4, 1820, after which it gained its independence from Massachusetts and became the 23rd state in the Union...

 to manage its eastern territories. In 1805 the northern portion of York County was separated to form part of Oxford County

Oxford County, Maine

Oxford County is a county located in the U.S. state of Maine with a population of 57,833 as of the 2010 U.S. census. Its county seat is Paris.Part of Oxford County is included in the Lewiston-Auburn, Maine, metropolitan New England City and Town Area while a different part of Oxford County is...

. When Maine achieved statehood in 1820 all of the counties of the District of Maine became counties of Maine.