Dietrich was employed as a clerk in a hardware store in
St. Joseph, Missouri. He moved to
Chicago, Illinois and engaged in the hardware business. He moved to
Deadwood,
Dakota Territory (now
South Dakota), in 1875 and engaged in mercantile pursuits, delivering goods on pack animals through the
Black Hills. He then located and owned the 'Aurora' mine. Dietrich settled in
Hastings, Nebraska, in 1878 and engaged in mercantile pursuits and in banking. Dietrich founded the German National Bank at Hastings and served as the president of the bank from 1887 to 1905. He became the president of the Hastings Board of Trade. Elected in 1900, Dietrich served as
Governor of Nebraska from January 3, 1901, to May 1, 1901. He resigned his governorship to replace interim U.S. Senator
William V. Allen, who had been appointed in 1899 after
Monroe L. Hayward died in office. His tenure in the Senate lasted from May 1, 1901 to March 3, 1905. His Senate service was most notable as a pro-
imperialist on the
Lodge Committee that investigated
war crimes during the
Philippine–American War. He did not run for reelection in 1904.
Bribery charge Before he assumed his Senate seat, Dietrich accepted money from Jacob Fisher in exchange for obtaining Fisher's appointment as a U.S. Postmaster. Dietrich and Fisher were charged with conspiracy to receive a bribe, accepting a bribe and profiting by the leasing of a building to the government. But before the trial could begin,
Judge Vandeventer held that Dietrich could not be prosecuted because the alleged bribery occurred after he was elected, but before Dietrich had been sworn in on December 2, 1901. All the charges were dropped, and Dietrich continued to serve as a US Senator from Nebraska. ==Death==