Horace Thorwaldson was born in Dupivog, Iceland, on Feb. 4, 1869. His father died in 1877, leaving a wife and ten children. In 1880, Thorwaldson's mother left Iceland with her children, settling in the Red River Valley of North Dakota, where they established a farm on the prairies of Pembina County.
In 1886, Horace left home and traveled to Seattle, where he apprenticed as a saddle and harness maker. He moved to Watsonville in 1893 and to Fresno in 1898, opening his own saddle and harness business.
In 1907, he sold his business and purchased a dairy in the Burrel area and a vineyard in Del Rey. He was appointed Chief Field Deputy by Sheriff Walter McSwain in 1911. Thorwaldson was appointed sheriff by the Board of Supervisors after the death of Sheriff McSwain in December 1915, and served out the remaining 37 months of McSwain's term. In 1918, near the close of World War I, Thorwaldson sought election as sheriff in his own right. In the election, with "Americanism" becoming an issue, Thorwaldson's Icelandic birth was counted against him, and William F. Jones was elected sheriff. Thorwaldson made a second unsuccessful run for sheriff against Jones in 1922. In the early 1920s Thorwaldson was appointed as a Deputy U.S. Prohibition Agent in the Fresno area. On December 19, 1926, after being promoted to Chief U.S. Prohibition Agent in the area, Thorwaldson was killed in an on-duty traffic accident at Manning and West. He was survived by his wife, son, and daughter.
During his period as sheriff, which was before national prohibition, Thorwaldson and his deputies were kept busy enforcing the Wyllie Local Option Law, a state law that had made most of Fresno County "dry." During World War I, the sheriff's office supported the national war effort by arresting "slackers," who failed to register for the draft. The second female employee in the history of the sheriff's office was hired by Thorwaldson in May 1917; Mrs. Josie Knot took over the duties of clerk-stenographer.
Thorwaldson was another "working sheriff," who handled most of the major criminal investigations during his tenure. The most noted homicide while he was sheriff was the March 1917 murder of Faustin Lassere in the National Colony by Charles and Anna Hammond. Thorwaldson also arrested the suspect in the hit-and-run death of Fowler Constable A.B. Chamness in September 1917. Throughout his incumbency, Thorwaldson was active in investigations of the radical socialist International Workers of the World. The Wobblies engaged in sabotage in the valley during the war, committing arsons of mills, packing plants, grain fields, and orchards to hamper the U.S. war effort. Late in his term, Sheriff Thorwaldson testified on important federal trials of I.W.W. leaders in Sacramento and Chicago.