William H. Illingworth

William H. Illingworth (20 September 1844 – 16 March 1893) was an English born photographer from St. Paul, Minnesota who accompanied both Captain James L. Fisk's 1866 expedition to the Montana Territory and Lt.

Shortly after Illingworth's return to St. Paul in 1866, he joined Captain James L. Fisk's fourth expedition to the Montana Territory.

Ludlow was the Chief Engineer of the Department of Dakota, and was in charge of mapping and scientific data collection for the expedition.

Illingworth and the U.S. 7th Cavalry Regiment departed for the Black Hills on 2 July 1874 from Fort Abraham Lincoln on the west bank of the Missouri River, seven miles south of what is now Mandan, North Dakota, and returned 30 August 1874.

While on the expedition, Illingworth produced about 70 glass plates – 60 of them were landscapes of the Black Hills and portraits of members of the 7th Cavalry.

When Illingworth escaped conviction on a legal technicality, Ludlow requested that the War Department press charges.