On 27 August 1914 he married the Swedish soprano Kerstin (Greta) Margaretha Jonsson, after he had met her at a Wagner performance in Rotterdam during an international tour.

At the beginning of World War I Van 't Sant was tasked with controlling foreign secret agents operating in Rotterdam.

Thanks to his ability to control foreign secret services and his dealings with Tinsley, at the age of 33 Inspector Van 't Sant was promoted to head-commissioner (Chief of Police) of the city of Utrecht in November 1916.

In 1918 the Germans approached him to establish contacts with the British government to begin the peace negotiations which brought the war to an end.

Van 't Sant was awarded Commander of the Most Excellent Order of the British Empire by King George V in January 1920, a rare honour for non-British citizens.

[1] In October 1920 Van 't Sant became head-commissioner of The Hague, a more prestigious post than Utrecht, as it involved regular contacts with the Royal House and key government figures.

Next to his only legitimate daughter Princess Juliana of the Netherlands, the future queen, Prince Henry had fathered several illegitimate children for which Van 't Sant had to make regular payments.

When the story of the secret tribunal broke via the National Socialist newspaper Volk en Vaderland, public outcry forced the authorities to an official criminal investigation.

In 1956 Van 't Sant admitted in an interview with historian Loe de Jong that he had scammed the Vredenburch family and had made up the story in order to spare the Royals another scandal.

On Sunday 12 May the Queen, accompanied by Van 't Sant, travelled to Hook of Holland and at 23.00 in the evening left the Netherlands on board of the British destroyer HMS Codrington.

Van 't Sant was not involved with the sending of Dutch agents into Holland by the SOE, which was being double played by the SD and Abwehr in the so-called Englandspiel.

Greet Hofmans was a female faith healer, hand layer and pacifist, who gained a lot of influence on Queen Juliana.

Although Prince-consort Bernhard, Prince of Lippe-Biesterfeld, had introduced Hofmans in 1948 to the queen in order to cure their youngest daughter, Princess Christina, he soon distrusted her and tried to send her away.

When this failed he leaked to the German magazine Der Spiegel, who published an article on 13 June 1956 which brought the affair in the open.

In 1977 Dutch film director Paul Verhoeven directed Soldaat van Oranje which was internationally distributed as Soldier of Orange.