In 1521, Portuguese explorers dubbed the massive body of water between Asia and the Americas the “Pacific,” on account of its peaceful waters. Unfortunately, the Pacific Basin has not always lived up to its name, witnessing a wide range of violent armed conflicts. This chapter provides an overview of armed conflict across the Pacific Basin, emphasizing varied patterns of violence. With some exceptions in East Asia, the Pacific Basin has seen few wars between states since World War II. In contrast, the Pacific Basin has seen a range of wars within states, primarily in Oceania, Southeast Asia, and Latin America. Here, there are distinct regional patterns, as Oceania and Southeast Asia have featured mostly ethnic violence, while Latin American armed conflicts tend to be ideological, in which communist rebels clash with authoritarian states. This chapter seeks to illustrate and explain these divergent regional patterns. It also emphasizes some good news—the decline of all forms of armed conflict across the Pacific.