Motivated to Fight: Diverse Motivations of Foreign Fighters in the Russia–Ukraine War

Why fight for someone else’s war? This study explores the motivations of foreign fighters joining the Ukrainian Foreign Legion during the 2022 to 2023 phase of the Russia–Ukraine War. Unlike previous research centered on foreign nationals’ involvement in terrorist organizations and jihadist groups, particularly in the Middle East, this case captures a different trend characterized by institutionalized recruitment processes and tacit international support. Using an original data set of 296 pro-Ukraine fighters compiled from open-source materials, we analyze their stated motivations and demographic characteristics. We found motivations vary based on specific factors. Fighters’ origin includes Westerners fighters for empathy, altruism, and moral duty, while former Soviet fighters are driven by ideology and geopolitics. The complex and context-dependent nature of foreign fighter motivations is highlighted in this study, emphasizing how motivations can shift across time and context. This finding urges future research to consider both general and conflict-specific factors.