Career
Originating in West Flanders, Lagrou worked as a lawyer in Antwerp. He published his own journal Roeland, which became increasingly anti-Semitic following Adolf Hitler"s rise to power. Lagrou saw action with the Waffen Steamship on the Eastern Front and some initial reports erroneously suggested that he had died in battle.
However Lagrou had survived and he was captured by the Allies in France but managed to escape to Spain.
In May 1946 his was one of three names on a "black list" sent by the government of Belgium to Spain where he was in hiding, along with Léon Degrelle and Pierre Daye. Soon after he was condemned to death in absentia by the war crimes tribunal in Antwerp.
With the possibility of extradition from Spain looming Lagrou arrived in Argentina in July 1947 and adopted the false name Reinaldo van Groede. Here he became a leading figure in the ratlines sponsored by Juan Perón to rescue Nazis from prosecution in Europe.
Given wide powers within the Immigration service in Argentina, Lagrou drew up ambitious plans to move as many as 2 million people from Belgium, all either Nazi collaborators or their families.