Troy is a town in Waldo County, incorporated on February 22, 1812 from Bridge's Plantation, formerly the township T4 R1 NWP.

The community has had a long succession of names. First incorporated as Kingville, it changed its name to Joy three years later in 1815, only to switch to Montgomery in 1826, and finally to Troy in 1827.

Those honored by these names were General Bridge of Massachusetts, an early proprietor, Governor William King, Benjamin Joy, an early proprietor, and English General Montgomery who died in the battle for Quebec.

Maine Route 220 joins U.S. Route 202/Maine Route 9 at Green's Corner near the shore of Unity Pond. Carleton Pond, Bog, and Stream are accessible from Route 220 in the north end of town.