Alternative history is a genre of fiction that explores what might have happened if key historical events had occurred differently. It imagines scenarios where pivotal moments, such as the outcome of a war or the decisions of influential leaders, take a different turn, leading to a changed world. This genre often examines the implications of these changes on society, culture, and politics. For example, a story might explore a world where Nazi Germany won World War II or where the American Civil War ended differently. These narratives encourage readers to think critically about history and its impact on the present.