Machiasport is a town in Washington County, Maine, United States. The population was 1,119 at the 2010 census. Machiasport is a historic seaport and tourist destination.
In 1633, the Plymouth Company established a trading post here to conduct business with the Native Americans. But this was part of Acadia, territory which New France considered its own. So in 1634, the trading post was sacked by French forces from Port Royal under the command of Charles de Saint-Étienne de la Tour. In 1770, the area was granted by the Massachusetts General Court to 80 petitioners, 54 from Scarborough. It was first part of Machias, incorporated in 1784, then set off and incorporated as Machiasport in 1826.
In 1775, following the capture of the British ship HMS Margaretta by locals under leadership of Jeremiah O'Brien, the residents built a small breastworks here to guard the mouth of the Machias River and the area settlements. Later that year, the British sent four ships under the command of Sir George Collier that defeated the local militia, destroyed the breastworks, and burned several buildings. In 1777, the fort was rebuilt as a crescent shaped four-gun battery.