|Extinct as a tribe|
|Regions with significant populations|
|Related ethnic groups|
The Nacotchtank were a native Algonquian people who lived in the area of what is now Washington, D.C. during the 17th century. Their principal village (also named Nacotchtank) was situated within the modern borders of the District of Columbia, on the eastern bank of a small river that still bears an anglicised variant of their name — the Anacostia.
The Nacotchtank seem to have been associated with the larger Piscataway, whose Tayac or grand chief ruled over a loose confederacy of area tribes. Another closely related tribe was the Doeg, whose homeland was on what is now the Virginia side of the Potomac, in the area around Fairfax, Prince William, and Stafford counties. All of these groups are thought to have spoken the Piscataway (or similar) variant of the Nanticoke language.
Encounters with the English 
The Nacotchtank were first recorded by Captain John Smith, who visited their palisaded village in 1608, and found them friendly. He noted that their main village had 80 fighting men, with a total population of about 300. It was an important trading center; tribes as distant as the Iroquois of New York would come to trade beaver pelts. The name Nacotchtank, existing in several historical variants including Nacostine, Anacostine, Anaquashtank, Nacothtant, Nachatanke etc., is said to mean "Trading village".
In 1622, Captain Henry Fleet took a party of English, together with their Patawomeck allies, to attack the rival Nacotchtank, killing 18 and burning their village. After the Nacotchtank took Fleet captive the following year, they held him for 5 years, during which time he learned their language. After escaping in 1628, he returned to Nacotchtank in 1632 and obtained "800 weight" of pelts.
He was told the Nacotchtank enjoyed a monopoly among area tribes on fur trade with the Iroquois. Fleet noted another of their villages called Tohoga, roughly the site of modern Georgetown. Two years later when the colony of Maryland was established, Fleet was still there as a trader, as related by the Jesuits.
Around 1668, greatly depopulated from Eurasian infectious diseases endemic to the English, to which they had no immunity, the Nacotchtank relocated to Anacostine Island (present-day Theodore Roosevelt Island.) Remnants and descendants likely merged with the Piscataway.
- Burr, Charles R. "A Brief History of Anacostia, Its Name, Origin, and Progress", Records of the Columbia Historical Society, 1920.
- Williams, Brett. "A River Runs Through Us," American Anthropologist, 103:2 (June 2001).