On May 10, 1940, Nazi Germany launched a surprise invasion of the neutral Netherlands, bombing Rotterdam’s historic center four days later and killing hundreds of civilians. The Dutch army surrendered on May 15, and the occupation began. Within months, anti-Jewish laws were introduced, and by July 1942, systematic deportations to concentration camps were underway. Across the country, ordinary citizens resisted in secret, hiding those in danger and risking their lives.
But others sided with the occupiers, and among them was a young woman who would become one of the most reviled figures in Dutch history. Florentine Sophie Houbolt was born on November 14, 1914, in Amsterdam, the youngest of four children. Her father was a German-born banker who had married his employer’s daughter and built a respected career in the Netherlands. The family lived in Hilversum, where they stood in high regard in the community, and Florentine once played tennis with the young Princess Juliana during a royal visit.
As a young woman, Florentine followed political developments in Germany with great interest. She read Hitler’s Mein Kampf and the writings of Nazi ideologue Alfred Rosenberg, and it is believed her German background shaped her strong orientation toward Germany. In the 1930s, she and her brother Wim joined the Nationale Jeugdstorm, the NSB’s youth organization modeled on the Hitler Youth. At the time, she was studying biology at Utrecht University, with a special interest in animal psychology.
In the summer of 1936, Florentine stayed in Berlin for her studies and was impressed by the Nazi movement firsthand, struck by its camaraderie, discipline, and commitment. After returning from a trip to the Dutch East Indies, she left the NSB because she believed racial hygiene was not being applied consistently enough and that party leader Anton Mussert did not share her concerns. That changed after the war began. When Germany invaded the Netherlands in May 1940, Florentine was working at a zoo in Berlin.
She returned home intending to contribute to the new regime. Shortly after the occupation, the NSB organized a large liberation meeting that she attended, and there she met Meinoud Rost van Tonningen, the second leader of the NSB. Under his influence, the party had become more oriented toward the Nazi party and adopted its anti-Semitic and racist ideology. Florentine was immediately impressed.
Rost van Tonningen proposed within months, but the relationship was complicated. He was 20 years older, already married with a child, and there were concerns about his racial purity because he was said to have Indian and Black African blood. Heinrich Himmler, head of the SS, eventually personally approved the marriage. The wedding took place in December 1940, attended by leading NSB figures.
In the early years of their marriage, Florentine held no public office, fulfilling representational duties as the wife of a high-ranking NSB member and giving birth to three sons in quick succession. Politically, the couple shared a clear vision: they believed the Netherlands was a lost part of Germany and should be incorporated into the German Reich. Other factions within the NSB disagreed, advocating instead for an independent Dutch state. During the occupation, Rost van Tonningen held one of the most powerful positions in the country.
In March 1941, he was appointed president of the Dutch Central Bank, where he removed currency barriers between the Netherlands and Germany and facilitated the transfer of Dutch gold reserves to the Third Reich. A wartime report noted he was convinced of the necessity of a greater European Economic Space, which made cooperation with German authorities easier. By 1944, with Germany clearly losing the war, Rost van Tonningen joined the Waffen SS. In March 1945, he was sent to the front as an SS-Obersturmführer, the equivalent of a first lieutenant in the U.
S. Army. Near the end of the war, Florentine fled with her children to the German town of Goslar, where her parents were also staying. The war in Europe ended on May 8, 1945.
Shortly after, Meinoud Rost van Tonningen died in prison while awaiting trial. He is said to have jumped over a stair balustrade, but Florentine always disputed that he committed suicide, claiming he was murdered. She alleged that, as president of the Dutch Central Bank, he knew too much about black market financial dealings involving prominent individuals, and she accused Prince Bernhard, husband of Queen Juliana, of bearing the main responsibility for his death. In July 1948, Florentine returned to the Netherlands.
She was arrested immediately but released a month later. With no income, she initially lived with a cousin in The Hague, managing his household. After 1950, her situation improved when she received a widow’s pension from the Dutch state because her husband had served in the Dutch parliament as an NSB member. She also inherited part of her German family’s wealth, enabling her to buy a villa in the town of Velp and start an electrical company.
Florentine maintained lifelong contacts with prominent ex-Nazis and sympathizers, including Gudrun Himmler, the daughter of Heinrich Himmler, and Paula Hitler, Adolf Hitler’s younger sister. During the 1950s and 1960s, she appeared on television several times, promoting the greatness of Hitler and Himmler and disputing the circumstances of her husband’s death. She also continued to publicly deny the Holocaust. In the 1970s, she became more politically active.
Her villa became a meeting place for old and new far-right supporters, and solstice celebrations held in the style of the Third Reich became notorious, earning her the nickname she had carried for decades: the Black Widow. In the early 1980s, a small circle of followers formed around her and established the Consortium de Levensboom, aimed at promoting Germanic culture. It published a periodical called Manuskripte that openly advocated National Socialism, reaching a peak circulation of 450 copies. During the same period, she was indirectly involved in founding the Center Party, helping collect signatures for the 1982 elections.
To finance these activities, she used funds from her business, which ultimately led to bankruptcy. She was almost continuously involved in legal proceedings. In 1986, a major public debate arose over her continued receipt of a widow’s pension, but a parliamentary vote decided that no special legislation was needed, allowing her to keep it. Her children always distanced themselves from her National Socialist ideology.
Florentine died on March 24, 2007, at the age of 92, in the Belgian town of Wassenberg, where she had spent her final years after struggling to find rental housing in the Netherlands. She was buried quietly in the Dutch town of Rheden to prevent an influx of neo-fascists. She left behind debts, and there was no money for her funeral.
