Okay, per Wikipedia: “Longfellow was inspired to write the poem after visiting the Old North Church and climbing its tower on April 5, 1860.” So it was the lanterns.
In addition: “Longfellow's family had a connection to the historical Paul Revere. His maternal grandfather, Peleg Wadsworth, was Revere's commander on the Penobscot Expedition.”
Until I played one of the Carmen games from 1995 with Lynn Thigpen, and I found a note left behind from one of her agents, I didn't realize that Carmen pays her people too Lol