Just War Theory (JWT) replaced an older warrior code, an approach to war that remains poorly understood and dismissively treated in the philosophical literature. This paper builds on recent work on honor to address these deficiencies. By providing a clear, systematic exposition of Honor War Theory (HWT), we can make sense of paradigm instances of warrior psychology and behavior, and understand the warrior code as the martial expression of a broader honor-based ethos that conceives of obligation in terms of fair competition for prestige. Far from being a romantic and outmoded approach to war, HWT accounts for current conflicts and predicts moral intuitions that JWT either rejects or cannot comfortably accommodate. So although it is not recommended as a replacement for JWT, there is good reason think that a fully mature, realistic, and yet properly normative theory of war ethics will incorporate a variety of insights from HWT.