Point of divergence

In discussion of counterfactual history, a point of divergence (POD) is a historical event, with two possible postulated outcomes. Typically these represent the actual course of historical events (Napoleon lost the Battle of Waterloo) and another, such as Napoleon won the Battle of Waterloo.

In alternative history fiction, the POD is used as the starting point for the extrapolation. For instance, in Philip K. Dick's The Man in the High Castle, the point of divergence is Franklin D. Roosevelt's assassination in 1933.

The multiverse theory posits that PODs are occurring all the time, with an infinite variety of possible outcomes that each creates a universe, this having been used as a premise to the 1990s US television series Sliders.