O.H. Tittmann (1850-1938) was a well known American surveyor during the late 19th and early 20th centuries. Born in Belleville, Illinois, Tittmann joined the U.S. Coast and Geodetic Survey in 1867 and enjoyed a long and distinguished career with this federal agency, serving as Superintendent of the Bureau of Weights and Measures (1889-1893) and Superintendent of the U.S. Coast and Geodetic Survey (1900-1915). In the course of his government career, Tittmann was involved in a number of notable surveying activities, which included serving as a member of an expedition to Japan to view the transit of Venus (1874), surveying the United States's east, west, and Alaska coasts, and serving as one of three scientists who investigated Admiral Robert Peary's claim of discovering the North Pole (1910). He also directed the surveys which established the boundary between the United States and Canada. After his retirement from the federal g overnment, Tittmann served as President of the National Geographic Society (1915-1919).

Charles T. Tittmann (1882-1964) was a lawyer and singer during the twentieth century. Born in Detroit, Michigan and educated at Princeton University and Harvard Law School, Tittmann served in the U.S. Army during World War I. After the war, he served as Assistant Solicitor with the U.S. State Department and practiced law in Washington, D.C. during the 1920s. From 1928 to 1953, he was an attorney for the U.S. Bureau of Internal Revenue. Tittmann was also a well known basso concert singer. He performed with numerous American symphony orchestras and was a soloist for the Bach Choir of Bethlehem, Pennsylvania.

Harry H. Tittmann (1893-1980) was an American diplomat during the twentieth century. A graduate of Yale University, Tittmann served as a pilot in the U.S. Army during World War I. Tittmann joined the United States diplomatic corps in 1920 and enjoyed a long career as a diplomat, serving assignments in France and Italy between the 1920s and 1940s. From 1941 to 1944, he served as U.S. Charge D'Affaires and President Franklin D. Roosevelt's personal representative to the Vatican. Tittmann later served other diplomatic assignments in Europe and South America before retiring in 1958.

Edward Tittmann (1906-1985) was a mining company executive during the twentieth century. Born in St. Paul, Minnesota and educated at Massachusetts Institute of Technology, Tittmann joined the American Smelting and Refining Company (ASARCO) as a chemist in 1929 and rose through the ranks of the company, serving as Ore Buyer and Assistant Manager of the company's Salt Lake City Office (1935-1941), Manager of the East Helena, Montana Smelter (1941-1947), Manager of the El Paso, Texas Smelter (1947-1952), and as General Manager of Western Smelting and Refining Department (1952-1955). From 1955 to 1959, Tittmann served as President of Southern Peru Copper Corporation, a joint venture involving ASARCO and several other mining companies. In this capacity, he was largely responsible for constructing and bringing into production a large open pit copper mine and copper mill near Ilo, Peru. Tittmann returned to the United States in 1959 and served as ASARCO's Executive Vice-Presid ent of Smelting and Refining (1959-1963) and as Chairman and Chief Executive Officer (1963-1971).