Merdeka Curriculum, the latest curriculum implemented in Indonesia by the Ministry of Education and Culture since 2021, faces obstacles in its implementation, including in history subject. A key obstacle history teachers encounter is the lack of alternative learning strategies designed to develop students' historical thinking skills. This study addresses this gap by formulating and examining a new strategy specifically designed to instill students' historical thinking skills named Problem Case Historiography, tailored to build critical historical reasoning abilities. This learning strategy integrates Problem Based Learning, Case Study, and Historiography concepts. This study aims to obtain new perspectives related to the implementation of Problem Case Historiography in historical learning within Merdeka Curriculum. This research was conducted in six senior high schools in Malang which have implemented the Curriculum. Data collection involved observing lessons and conducting interviews with teachers and students. The observational findings revealed increased student enthusiasm and participation during Problem Case Historiography. The results of the interviews also showed that they were pleased with the learning strategy applied, due to its clearly described procedures which could train them how to think like historian, so that their historical thinking skills could be stimulated. [For the complete proceedings, see ED672804.]