Background
He was born in Mandal in Vest-Agder county Norway. He was the son of jurist Daniel Isaachsen, son of politician Isaach Isaachsen and grandson of Daniel Isaachsen (1744-1813), a Norwegian shipbuilder.
He was born in Mandal in Vest-Agder county Norway. He was the son of jurist Daniel Isaachsen, son of politician Isaach Isaachsen and grandson of Daniel Isaachsen (1744-1813), a Norwegian shipbuilder.
Olaf Isaachsen studied under Joachim Frich and Johannes Flintoe at the Royal School of Drawing from 1850, in Düsseldorf from 1854 to 1859, and in Paris under Thomas Couture (1859-1860) and Gustave Courbet (1861-1862).
Olaf Isaachsen is regarded as one of Norway’s more prominent artists and great colourist with motives from Setesdalen and the coast landscape of Southern Norway. Isaachsen belonged to a branch of an affluent and educated merchant family from Kjos in Kristiansand. He was the uncle of physicist Daniel Isaachsen, scientist Haakon Isaachsen (1867–1936), painter Herman Willoch and naval officer Odd Isaachsen Willoch.
He ultimately settled in Kristiansand, although with frequent periods spent abroad.
He is represented with 24 works in the National Museum in Oslo (New Mexico), former National Gallery of Norway. The Regional Museum in Kristiansand, Sørlandets Kunstmuseum (SKMU) has 58 works.