Christopher was the Director of Learning and Teaching within the Department between August 2022 and August 2025. In this role he was responsible for overseeing the strategic development of the learning and teaching environment within the department and coordinating undergraduate and taught postgraduate provision.

He previously acted as Deputy Director of Undergraduate Studies within the department between September 2019 and August 2021. In this role he was responsible for chairing the undergraduate examination boards and overseeing the department's adherence to University Special Circumstances policy.

Christopher currently contributes to the Student Experience portfolio within the Department.

Christopher joined the Department of International Politics in January 2019, having previously taught History at the University of Huddersfield and Leeds Trinity University. His first monograph, entitled Civilian Specialists at War: Britain's Transport Experts and the First World War was published in April 2020 by the University of London Press as part of the New Historical Perspectives series. It was a runner up in the First Book category in the Society for Army Historical Research's annual book awards in 2021.He has also produced material for a range of scholarly and popular publications. His research interests cover military logistics, the evolution of warfare in the modern era, the British Army, and global conflict. His previous research has focused on the intersections between the state, the military, and private enterprise, the influence of logistics on military operations, and the development of professional military education. He is currently working on a monograph exploring how Britain's experiences of both preparing for and fighting the First World War can provide insights into the challenges that may confront the British government, armed forces, and wider society in the event of a major conflict in the future.

Christopher currently teaches on both undergraduate and postgraduate modules within the Department of International Politics. He is primarily responsible for teaching modules relating to military history and the history of warfare more broadly, but has also contributed to the Department's teaching of contemporary warfare and strategic studies.

Christopher is a Fellow of both the Royal Historical Society and the Society for Army Historical Research.