Morton Abramowitz, a former American diplomat and conflict mediator whose efforts to end and avoid wars, included helping to arm anti-Soviet guerrillas in Afghanistan in the 1980s, and founding the International Crisis Group for peace in the 1990s, died Nov. 29 at home in Washington, D.C. He was 91.

As an adviser, analyst and three-time ambassador, Mr. Abramowitz influenced U.S. policymaking in Europe and Asia, and helped forecast shifting priorities as the Cold War ended and other challenges emerged, including Islamist extremism and China’s rise as an aspiring superpower.

After retiring from government service in 1991, he took on the role of statesman emeritus as head of the Carnegie Endowment for International Peace and the International Crisis Group.