The area was once territory of the Penobscot tribe of the Abenaki people, which each summer visited the seashore to hunt for fish, shellfish and seafowl.

[4] Waldo died in 1759, and his heirs would sell the plantation of Passagassawakeag (named after its river) to 35 Scots-Irish proprietors from Londonderry, New Hampshire.

Materials for wooden boat construction were shipped down the Penobscot River from Bangor, the lumber capital of North America during the later 19th century.

[6] Shipbuilders became wealthy, and built the Federal, Greek Revival and Italianate mansions and civic architecture for which the city is noted, including the 1818 First Church by master-builder Samuel French, and the 1857 Custom House and Post Office by noted architect Ammi B.

Wooden ship construction would fade by about 1900, but with the advent of ice harvesting and refrigeration, the local economy shifted to distributing seafood, including lobsters, scallops, sardines, herrings and mackerel for the Boston and New York markets.

Regular passenger service ended in 1960, and all operations in Belfast of any kind ceased in 2005, when the main yard was torn up.

[11] In 2011 the grounds of the former B&ML main yard and adjacent Stinson Seafood factory became the site of the Front Street Shipyard.

The railroad's 1946 vintage engine house was torn down and its site is now occupied by the shipyard's 26,500 sq ft (2,460 m2), five-story boatbuilding and repair facility.

The annual Broiler Festival became a popular summer event, attracting both local people and tourists.

In the early 1980s, the defunct chicken-feed silos at the foot of Main Street, that once fed millions of chickens, were demolished.

[13] In the early 1990s, credit card giant MBNA established two facilities in Belfast, one considerably larger than the other.

Jobs provided by MBNA, which was acquired by the Bank of America, helped increase Belfast's population significantly.

In 1996, shipbuilding was re-established on the Belfast waterfront with the opening of French & Webb, Inc., classic wooden yacht builders and restorers.

Following in their footsteps, Front Street Shipyard opened a major boatyard on the Belfast Bay in 2013.

Together, the two boatbuilding companies have restored Belfast's working waterfront and helped revive the city economy as well as appeal to tourists.

Belfast is bordered by Waldo and Swanville to the north, Searsport to the east, Northport to the south, Belmont to the southwest and Morrill to the west.

This climatic region is typified by large seasonal temperature differences, with hot and humid summers and cold and dry winters.

Towns in the new RSU #20 District as of fall 2009 that were combined with MSAD #56: Disagreements over inflating costs and the lack of local control over their students education caused several towns across Maine to consider withdrawing from these larger consolidated districts.

Belfast voted in February 2014 to spend $25,000 to put together a report on the educational and financial impacts of leaving RSU 20.