But we missed an important moment back in October:
"OCTOBER, 1814.
Sat. 15 . . . This day the H. of R. Negotiated a bill for the removal of the seat of Government."
But what does this mean?
During the War of 1812, the British attempted to burn down Washington, DC. They successfully torched the unfinished Capitol building, leaving it just a shell. The 13th Congress returned to DC for the next session and had to move their meetings to the Patent Office.
Many of the legislators wanted to move the government out of Washington, DC. Legislation took a long time, and finally, on October 15, 1814, nine votes kept the capital in DC. Congress met in various places around the city for several years until the Capitol could be rebuilt.
For more information about this, read the House of Representatives' blog post, "Leave No Forwarding Address: When Congress Almost Abandoned D.C.".