Though largely unknown, the 1980 Convention on Certain Conventional Weapons (CCW) has been successful in many areas. The treaty remains in force today and has helped to regulate many types of weapons, including landmines, incendiary weapons, and blinding laser weapons. Additionally, it has helped to clarify terms important for international legal norms, such as “unnecessary suffering” and “military necessity.” The CCW was the first treaty to regulate conventional weapons in more than 70 years. Why is this seemingly useful treaty relatively unfamiliar compared with other laws of war treaties, remembered only by humanitarians who occasionally invoke it to denounce it for being conservative or even a “humanitarian failure”? This article shows that besides “humanitarian politics,” Cold War politics had a major and underappreciated impact on conventional weapons treaty negotiations from the late 1960s through the 1980s. In particular, Cold War politics established the different sides in the negotiations (West, East, and South), which had a far-reaching impact on the conduct and tone of the negotiations, determined the weapons and issues under discussion, and ultimately affected implementation of the 1980 CCW following its ratification. By tracing the history of conventional weapons negotiations from 1968 to 1980 and examining the key impact of Cold War politics on the process, this article sheds light on the politics of conventional weapons negotiations today.