Mark T. Gilderhus, a professor of U.S. diplomatic history, died at his home in Fort Collins on Thursday, January 22, of cancer. He taught at Colorado State University for 29 years, serving as the chair of the History Department from 1980 to 1993. In 1997, he accepted the Lyndon Baines Johnson Chair in History at Texas Christian University, where he served in this capacity until his retirement in 2010. He was the author of numerous articles and books, and described himself as a "scholar of war, politics, and diplomacy." Mark had a wonderful sense of humor, a generous spirit and was a kind colleague and friend. He was also a loving husband, father, and brother. He is survived by his wife, Nancy Gilderhus, of Fort Collins, and his two daughters: Kirsten Gilderhus, of Fort Collins; Lesley Jones, of Fort Collins; and three grandchildren Della Fisher, and Morgan and Jake Jones. He also is survived by a sister, Susan Zakeer, of Blaine, MN. Memorial donations may be made to Society for Historians of American Foreign Relations (SHAFR) with a note in memory or honor of Mark Gilderhus, and sent to Professor Peter Hahn, Executive Director of SHAFR, Department of History, Ohio State University, 106 Dulles Hall, 230 West 17th Avenue, Columbus, OH 43210. A memorial service will be held at 3:30 p.m. Saturday, Feb. 21 at the Columbine Room in the Lincoln Center, Fort Collins. Visit bohlenderfuneralchapel.com to view the full obituary and send condolences.