Kaiserreich is a popular alternate history mod for the video game Hearts of Iron IV. It imagines a world where the Central Powers won World War I, leading to significant changes in global politics and national borders. The mod features a complex narrative with various factions, countries, and leaders, allowing players to explore different historical outcomes. In this alternate timeline, major powers like Germany, Austria-Hungary, and Ottoman Empire maintain their influence, while countries such as Russia and France face different challenges. Players can engage in diplomacy, warfare, and economic management, shaping the future of their chosen nation in this reimagined world.