In 1841 and 1842, "unfortunate political differences . . . agitated the people of Rhode Island." This is how the U.S. Supreme Court described that dispute over which government was the legitimate government of the state of Rhode Island, that divided the state into armed camps.
The legitimacy issue had been resolved before the case reached the U.S. Supreme Court, and the dispute hasn't made it into many history books or even constitutional law texts. But, the story is laid out at length in a majority and dissenting opinion discussing an intentional tort lawsuit brought in federal court in the wake of this near civil war in the early days of Rhode Island's accession to the United States.
If you still aren't sated, you can read about the constitutional law relevance of dueling.