[2] Born in St. Louis, Missouri, Heitfeld attended public and private schools there.
He was elected as a Populist to the United States Senate in 1896, served a single term, and did not seek reelection in 1902.
From 1914 to 1922, Heitfeld was a registrar of the United States General Land Office at Lewiston.
At age 71 in 1930, Heitfeld returned to politics as a member of the Nez Perce County Commission, eventually serving as its chair.
Heitfeld's funeral was in Lewiston at St. Stanislaus Catholic Church, and he was buried in Normal Hill Cemetery, next to his wife.