Helmuth was a refugee from Germany. He arrived in the Netherlands on January 3rd, 1939. He stayed in Rotterdam (hotel Holland America Lijn) and went to Wieringen in November 1939.
He was not a Zionist and learned in the smithy.
His last address in Germany was Adolf Hitlerstr. 87, Kerpen b/Köln.
Source: National Archives, 2.04.58, inv. 130 and others
Another source of information is http://www.dokin.nl/deceased-children/helmuth-leiser-born-1-sep-1923