On the centennial of the peace treaty that ended the Russo-Japanese War of 1904-5, Dartmouth College hosted a conference to examine the background and making of that treaty and its long-term implications for international relations. Over forty North American, Japanese, and Russian scholars and practitioners participated in the forum. The Treaty of Portsmouth and Its Legacies presents eight outstanding conference papers, revised for publication, and two additional papers solicited to round out the scholarship. Together these papers illuminate diplomacy before and after the war, the peace process, the political and cultural legacies of Portsmouth, and the treaty's significance for Asia-Pacific relations today.