The chronological biography or ‘Nianpu’ is a special style of Chinese historical writing formed by a person’s life events in time order. It provides significant records for the research of historical events. However, from syntactic collation, structural, and semantic aspects, the heterogeneousness of Nianpu materials caused the lack of systematical information collation, which could hinder the research of historical events. The article presents a semantic WebGIS platform based on an entity-oriented search and visualization system to reorganize unstructured information. It delivers: (1) a Chinese historical event database to store and manage Chinese historical information derived from the chronological biography; (2) an ontology to integrate different historical datasets; and (3) a web geographic information system to visualize and analyze information of historical events. This platform achieves the reorganization of historical event information at spatial and temporal levels by the Web. It enables humanities researchers to explore the relationships of historical entities and their evolution visually and interactively. The platform is available at https://nianpu.pkudh.org/.