Before he could finish his ride, Revere got busted by the British. They took his horse, and he had to walk back to Lexington (source).
Longfellow fudged the lantern story a bit. Actually it was Revere himself who hung the lanterns in the church and then rode out to warn the countryside (source).
Longfellow had his own connections to the American Revolution. In Boston he lived in a house that had been George Washington's headquarters for nine months in 1775 (source).
Henry's mom's name was Zilpah. No word on whether she was an alien (source).