Theatrical Memory in Hungary is a groundbreaking project created in 2018 by the Hungarian Theatre Museum and Institute (OSZMI-PIM), in which a group of theatre historians prepared a complex historical investigation of three Hungarian theatres. The project has published its initial results, including articles and oral history interviews. The new theatre history portal is based on a complex, relational database of the museum’s digitized inventories. The aim of the project was to create a new user-friendly interface, to publish the digitized information from the databases of the Hungarian Theatre Museum and Institute, providing multi-faceted search and browse facilities for experts and the public alike. The portal displays the metadata and the full content together, seeking to display the complex network of datalinks which connect the elements of the database. We have implemented 26 individual knowledge base systems which extend beyond the regular library and museum repositories, using special authority records (theatre company, theatre and performance) in the semantic MARC framework of one single Huntéka museum system. The newly developed data model also has the potential for a FRBR level repository. The database collecting the performances, theatre companies, theatre data, critiques, and recordings of performances is available on the theatre portal (www.szinhaztortenet.hu). The portal offers new possibilities for researchers and is of great interest to the public. The structure of the portal facilitates new ways of browsing. The available studies and the wide range of documents stored in the database are closely linked, offering forward-looking opportunities for researchers to present and disseminate information on the history of these theatres.