Signed and dated front lower right

The son of a Royal Irish Artillery officer, William Armstrong studied art in Dublin and served his apprenticeship as an engineer on the Irish and English railways before immigrating to Toronto in 1851. He was partner in the firm of Armstrong, Beer, & Hine Civil Engineers, Draughtsman and Photographers. Armstrong traveled to Lake Superior in 1859 and from then on took advantage of surveying work to travel and sketch extensively in lands then unsettled by Europeans. He took particular interest in the native populations of the northern plains, such as the Assiniboin and the Sioux, glimpsed in the years immediately prior to their confinement to reservations. Fort William provided him with the opportunity to document the evolving commerce of the area. The Assiniboin natives had an important role in the local commerce - the fur trade - for it was their technology, especially the birch bark canoe and snowshoe, which enabled the Europeans to succeed. Armstrong's most sought after watercolours are those which he worked up from sketches completed during his travels in 1859 to Fort William (now the city of Thunder Bay, Ontario, Canada). Many of these watercolours were presented to the Prince of Wales on his visit to Toronto in September 1860.  In 1870, Armstrong accompanied the Wolseley Expedition to the Red River Colony, recording the incredible effort required to move the military force through the Canadian wilderness. One of his compositions, Red River Expedition, Purgatory Landing was reproduced as a wood engraving on the cover of the Canadian Illustrated News on July 9, 1870 to accompany their coverage of the expedition's progress. He won numerous prizes as an artist at provincial exhibitions, and his work was displayed at the Exposition Universel le in Paris in 1855,
and at the Dublin International Exhibition, 1865. He exhibited with the Ontario Society of Artists and was a member of the Royal Canadian Academy of Arts until 1887, when he resigned.  In 1864 Armstrong began to teach drawing at the Toronto Normal School. He taught at the University of Toronto from 1872 to 1877. He retired in 1897 but continued teaching art from his home until his death.