Dissertation Summary: Why do some territorial claims erupt in armed conflict while states are able to prevent others from militarizing? Scholars have argued that territoriality—or the propensity for people and societies to occupy, develop emotional attachment to, and defend land—exacerbates international political crises. However, this research tradition treats territoriality as a universal characteristic. It therefore cannot account for variation in how states manage territorial disputes. The dissertation argues that institutions mediate the expression of territoriality, with some increasing the odds that a border dispute will spark violence. A large-N study (1946-2008) examines how different regimes militarize territorial claims. A historical case analysis looks at how asymmetric information about territorial quality negatively affects interstate bargaining. The final paper theorizes that territoriality spuriously correlates with territorial violence. Instead, loss aversion accounts for the bloodiest border clashes.