what was the reason behind this raid?
It was a result of the ongoing conflict between the United States and its allies, and the United Kingdom of Great Britain and Ireland and its allies.
War of 1812
The War of 1812 was a conflict fought between the United States and its allies, and the United Kingdom of Great Britain and Ireland and its allies. 
what does the dc in washington dc stand for District of Columbia. how is the place widely as? The capital city of the United States of America. what happened to this place in 1812? On August 24–25, 1814, in a raid known as the Burning of Washington, British forces invaded the capital during the War of 1812.
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War of 1812 [SEP] Introduction
The War of 1812 was a conflict fought between the United States and its allies, and the United Kingdom of Great Britain and Ireland and its allies. It began when the United States declared war in June 1812 and ended in a stalemate when a peace treaty agreed to earlier was ratified by the United States in February 1815. While the war ended in a draw, both sides were happy with the outcome that saw the war ending, although indigenous nations are generally seen among historians as the real losers. Historians in Britain often see it as a minor theatre of the Napoleonic Wars while historians in Canada and the United States see it as a war in its own right.