Gabriel Von Hackl was capable of highly detailed portraits and scenes but also painted in a more impressionistic style in the later part of his career. He was accomplished at anatomy due to his studies at the University of Vienna.

In 1865, he moved to Munich and attended the Akademie der Bildenden Künste where he studied under Alexander Wagner and Carl Theodor von Piloty. Between 1878 and 1919, he worked as a teacher at the Münchner Kunstakademie and several of his students went on to become successful. He was known as a particularly tough taskmaster - particularly with anatomical studies.