Weltbau

Weltbau is a term used to describe the deliberate construction of a fictional world for storytelling, games, or simulations. In German, the more standard form is Weltenbau; Weltbau appears in some texts as a variant. The practice encompasses geography, history, cultures, technology, magic or science, religions, languages, politics, and the laws of nature within the imagined setting. The goal is internal consistency and plausibility, enabling coherent plots and gameplay across media.

Practitioners often create a world bible or lore bible—an organized collection of timelines, maps, cultural descriptions, genealogies, and rule systems. This documentation helps maintain canonical coherence, while allowing writers and designers to decide which details are essential to the narrative and which can remain flexible. Tools commonly used include world maps, chronological timelines, cultural lexicons, language sketches, and systems for magic, technology, and economy.

Weltenbau is prominent in fantasy and science fiction, but also features in tabletop role-playing, video games, and films. It supports world-specific constraints, such as magical laws, technological level, and socio-political structures, and it can be developed iteratively as a story grows or as gameplay scales. Notable challenges include avoiding over-detailed world-building that slows narrative pace and ensuring that the constructed world enhances rather than distracts from characters and themes.