Map - Martha's Vineyard (Martha's Vineyard Island)

Martha's Vineyard, often simply called the Vineyard, is an island in the Northeastern United States, located south of Cape Cod in Dukes County, Massachusetts, known for being a popular, affluent summer colony. Martha's Vineyard includes the smaller adjacent Chappaquiddick Island, which is usually connected to the Vineyard. The two islands have sometimes been separated by storms and hurricanes, which last occurred from 2007 to 2015. It is the 58th largest island in the U.S., with a land area of about 96 sqmi, and the third-largest on the East Coast, after Long Island and Mount Desert Island. Martha's Vineyard constitutes the bulk of Dukes County, which also includes the Elizabeth Islands and the island of Nomans Land.

The Vineyard was home to one of the earliest known Deaf communities in the United States; consequently, a sign language, the Martha's Vineyard Sign Language, emerged on the island among both Deaf and hearing islanders. The 2010 census reported a year-round population of 16,535 residents, although the summer population can swell to more than 750,000 people. About 56 percent of the Vineyard's 14,621 homes are seasonally occupied.

Martha's Vineyard is primarily known as a summer colony. However, its year-round population has considerably increased since the 1960s. The island's year-round population increased about a third each decade from 1970 to 2000, for a total of 145 percent or about 3 percent to 4 percent per year (46 percent, 30 percent, and 29 percent in each respective decade). The population of the Vineyard was 14,901 in the 2000 Census and was estimated at 15,582 in 2004. (Dukes County was 14,987 in 2000 and 15,669 in 2004). Dukes County includes the six towns on Martha's Vineyard and Gosnold; it increased by more than 10 percent between 2000 and 2010, according to Census data released in 2011, gaining nearly 1,548 residents. The Island's population increased from 14,987 to 16,535.

A study by the Martha's Vineyard Commission found that the cost of living on the island is 60 percent higher than the national average, and housing prices are 96 percent higher. A study of housing needs by the Commission found that the average weekly wage on Martha's Vineyard was "71 percent of the state average, the median home price was 54 percent above the state's and the median rent exceeded the state's by 17 percent," all leading to a stark example of severe income inequalities between year-round residents and their seasonal counterparts.

There is no definitive source for the name 'Martha's Vineyard', but it is thought to be named for the mother-in-law or daughter, both named Martha, of the English explorer Bartholomew Gosnold, who led the first recorded European expedition to Cape Cod in 1602. A smaller island to the south was first to be named "Martha's Vineyard" but this later became associated with this island. It is the eighth-oldest surviving English place-name in the United States. The island was subsequently known as Martin's Vineyard (perhaps after the captain of Gosnold's ship, John Martin); many islanders up to the 18th century called it by this name.

When the United States Board on Geographic Names worked to standardize placename spellings in the late 19th century, apostrophes were dropped. Thus for a time Martha's Vineyard was officially named Marthas Vineyard, but the Board reversed its decision in the early 20th century, making Martha's Vineyard one of the five placenames in the United States that take a possessive apostrophe.

According to historian Henry Franklin Norton, the island was known by Native Americans as Noepe or Capawock. It is referred to in the 1691 Massachusetts Charter (which transferred the island from Province of New York during the breakup of the Dominion of New England) as Cappawock.