Gaus was born and grew up in Braunschweig where his parents, Willi and Hedwig Gaus, owned and ran a successful fruit and vegetable retail business. Alongside the conventional greengrocer merchandise there was a complementary specialist section with a focus on . Many years later his journalist-daughter would tell an interviewer that wartime experiences of numberless nights spent in bomb shelters and, in particular, of the destructive English air attack of 15 October 1944, would have a lasting impact in the child. Gaus was born a couple of months too early to avoid more active participation in a war. Shortly before it ended he was sent for two weeks as part of a large school-boy contingent to the Netherlands "to dig trenches" (intended, it would appear, to serve as "tank traps").