Though Power was born in New Zealand, his parents returned to Australia soon after. His father taught painting in Brunswick, Victoria, but tried to discourage his son's interest in art. However, at the age of fourteen Harold Septimus Power ran away from home and went into the bush to paint country scenes and animals. After trying a number of trades, he decided to become an artist. In 1896 he won a silver medal at the Collingwood Junior Exhibition in Melbourne. In 1899 he won another silver medal, as well as a gold medal at the Melbourne Art Club exhibition. In 1900 he moved to South Australia, where he became a political cartoonist with the Adelaide Register. Power's sketches began appearing in other Adelaide newspapers, the Observer, Saturday Journal and Evening Journal, around the year 1902. They include witty drawings of parliamentarians, sympathetic portrayals of street scenes and historically valuable comments on local identities. In 1903 he received the first commission given by the National Gallery of South Australia to an Australian artist.
In 1904 Power enrolled at Julien's Academy in Paris. Her then went to London, where he found some success with his paintings. He became a regular exhibitor at the Royal Academy. In 1913 he returned to Australia, where he held two successful exhibitions of the work he had painted while overseas. His reputation grew, and in 1915 the Government of Australia invited him to become one of the first two official war artists. His paintings of battle scenes, created as they occurred, hang in major galleries and war memorials throughout the world. In 1922 he won an Australia-wide competition to paint a mural, 15.2 metres long by 2.6 metres high, depicting the Eastern and Western fronts of the war, for the entrance to the Science Museum in the Melbourne Public Library. By 1935 he was one of Australia's most renowned artists. For the rest of his life he travelled between England and Australia, as well as regularly visiting France and America.
