His work was among those considered degenerate art by the Nazis, but after World War II he regained recognition as one of the leading German painters.

Four weeks after his birth, his father, the military musician Karl Friedrich Hofer, died of a lung disease.

In 1902 Hofer concluded a five-year contract with the Swiss entrepreneur and patron Theodor Reinhart, in which it was agreed a regular support.

During the summer of 1914, during a stay in the French seaside resort of Ambleteuse, the Hofers were surprised by the outbreak of World War I and were interned because of their citizenship.

On April 1, 1933 Hofer was defamed in a poster together with Oskar Schlemmer and other teachers of the Berlin Art Academy as "representatives of the decomposing liberal-Marxist-Jewish alliance".

Despite his rejection of National Socialism, Hofer believed that his art could be accepted by the regimen, because he understood it as being German.

In the exhibition of the Berlin Secession in the summer of 1933, the catalog preface said that German art was expressed in Hofer's painting.

[3] Hofer was represented with eight works in the Nazi propaganda exhibition "Degenerate Art" held in Munich, in 1937.

Hofer was expelled from the Reich Chamber of the Fine Arts in October 1938, since the confirmation of the divorce came too late at the Ministry of Propaganda.

He was then no longer allowed to sell his works publicly in the art trade or at auctions; the exclusion was therefore considered a professional ban.

In November 1938, Hofer married for a second time to Elisabeth Schmidt, considered an "aryan" according to Nazi standards.

After the divorce, his ex-wife Mathilde was no longer protected for being in what the Nuremberg Laws called a "privileged mixed marriage", and was deported to the Auschwitz concentration camp, where she was killed on 21 November 1942.

After the end of World War II, Hofer was involved in the construction of the Berlin Academy of Fine Arts, whose director he became in July 1945.

Hofer published two autobiographical books, Aus Leben und Kunst (Of Life and Art), in 1952, and "Erinnerungen eines Malers" (A Painter's Memories), in 1953.

The controversy led Ernst Wilhelm Nay, Willi Baumeister and Fritz Winter, to withdraw from the Deutscher Künstlerbund.

Hofer planned to publish the treatise Über das Gesetzliche in der bildenden Kunst (On the Lawful in Fine Art), on the controversy, because in the same year, at the climax of the dispute, he suffered a stroke, from which he succumbed later.