A clash between the U.S. and Britain - always sure to fuel argument on the forum as to this day people disagree on who won, lost, or achieved a draw in the war. It also settled very little, perhaps another reason for its popularity in AH discussion.
Below is an overview of points of divergence concerning this military conflict.
Points of Divergence : American Revolutionary War
Points of Divergence : Napoleonic Wars
Points of Divergence : American Civil War