Heinz was the son of Alois Hitler Jr. and his second wife Hedwig Heidemann, whom he had married bigamously.

Heinz was a strong supporter of the Nazis and Adolf Hitler reportedly called him his favorite nephew.

Allegedly, Heinz had insisted on serving on the front line against the wishes of Hitler.

On 10 January 1942, after a retreat by the Wehrmacht, Heinz was ordered to recover radio equipment from an abandoned post.

He was captured by Red Army forces during the mission and was taken to the Butyrka military prison in Moscow.