He came to the Royal Danish Academy of Fine Arts in 1878, completing his course of study in five years. He made his debut at the Charlottenborg Spring Exhibition in 1883. Two years later, he joined a study trip across Italy to Egypt, Palestine, Greece and Turkey. Later he visited Scotland, England, Holland, Belgium, Spain, Morocco and France. With support from the Cultural Ministry, he traveled to the Exposition Universelle (1889) in Paris. He was awarded the Eckersberg Medal in 1890 and 1899. He became an assistant at the Royal Danish Academy from 1893–1905 and worked periodically as a conservator-restorer. Ilsted died in Copenhagen during 1933.