In 1960, President Dwight D. Eisenhower appointed Timberlake to the position of first U.S. Ambassador to the newly independent Democratic Republic of the Congo, a former Belgian colony. During the Congo Crisis, Hayes was a vocal supporter of Mobutu Sese Seko, and advocated the deposition of Patrice Lumumba. In March 1961, Hayes personally ordered five U.S. Navy vessels into the waters off the Congo, a move that caught the Kennedy administration off guard.