When did Maine become a US state?

== == Maine's statehood came about as a result of the Missouri Compromise. The crux of the debate was that neither the pro-slavery nor anti-slavery side wanted its opponents to gain ground in terms of the number of free or slave states. Politics ruled, and a compromise prevailed. For every non-slave state there had to be a slave state for balance. After much negotiation and discussion, it was agreed that Maine, which had been part of Massachusetts, would be admitted to the Union as a free state and Missouri was admitted as a slave state. All land west of Missouri's southern border was made free. Delegates met for three weeks in October of 1819 in Portland, Maine, to hammer out a state constitution. In late February 1820, the bill for Maine statehood passed both houses of the US Congress. It was then sent to the President for approval. On March 3, 1820, the President signed the bill. Maine became the 23rd state to join the union. Portland was selected as the state capital, but this was temporary. In 1832 the capital was moved to Augusta, a more centrally located site.