Florentine Rost van Tonningen was born Florentine Sophie Houbolt on November 14, 1914, in Amsterdam, the youngest of four children. Her father was German, had moved to the Netherlands as a young man to build a banking career, and married his employer's daughter. The family settled in Hilversum, where they were held in high regard.
As a young woman, Florentine followed political developments in Germany with great interest. She read Adolf Hitler's manifesto Mein Kampf and the writings of Nazi ideologue Alfred Rosenberg. Her German background is believed to have driven her strong orientation toward Germany.
In the 1930s, she and her brother Wim became active in the Nationale Jeugdstorm, the youth organization of the Dutch fascist party, the NSB, which was modeled on the Hitler Youth. She studied biology at Utrecht University, with a special interest in animal psychology.
Hitler and his Nazi party came to power in Germany in January 1933. In the summer of 1936, Florentine stayed in Berlin for a period connected to her studies. There she was impressed by the Nazi movement firsthand and struck by its camaraderie, discipline, and commitment.
A year later she traveled to the Dutch East Indies. After returning to the Netherlands, she left the NSB because she believed racial hygiene was not being applied consistently enough within the party and that party leader Anton Mussert did not share her concerns.
The Second World War began on September 1, 1939, when Nazi Germany invaded Poland. For eight months the Netherlands remained neutral, hoping to stay out of the conflict. That hope ended on May 10, 1940, when Hitler launched a surprise attack without a declaration of war.
German paratroopers seized key bridges and airfields while the Luftwaffe bombed Rotterdam, killing hundreds of civilians and destroying the city's historic center. Faced with the threat of similar devastation elsewhere, the Dutch army surrendered after just five days. Queen Wilhelmina and the government fled to London, and the Nazi occupation began.
In the spring of 1940, Florentine was working at a zoo in Berlin. Upon hearing of the occupation of the Netherlands, she returned home intending to contribute to the new regime.
Shortly after the invasion, the NSB organized a large meeting. Among those present were Florentine and Meinoud Rost van Tonningen, a prominent NSB member and radical national socialist. He was the second leader of the NSB, and after 1936, under his influence, the party became more oriented toward the Nazi party and adopted its anti-Semitic and racist ideas.
Florentine was introduced to Rost van Tonningen and was immediately impressed. A few months after their first meeting, he proposed. The relationship was not without complications: he was 20 years older than her, already married with a child, and there were concerns about his racial purity, as he was said to have Indian and black African blood. Heinrich Himmler, head of the SS, eventually personally approved the marriage.
The wedding was held in December 1940 and was attended by leading NSB figures. In the early years of their marriage, Florentine held no public office. She fulfilled the representational duties expected of the wife of a high-ranking NSB member and gave birth to three sons in quick succession.
Politically, the couple shared a clear vision. Both believed the Netherlands was a lost part of Germany and should be incorporated into the German Reich. Other powerful factions within the NSB held very different views and remained committed to Dutch nationalism, advocating instead for an independent Netherlands.
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, a role in which 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 that he was convinced of the necessity of creating a greater European Economic Space, which made cooperation with German authorities easier.
In 1944, as it became clear that Germany was going to lose the war, Rost van Tonningen joined the Waffen SS, the military branch of the SS. In March 1945, he was sent to the front as an SS-Obersturmführer, the equivalent of a first lieutenant in the US Army.
Toward the end of the war, Florentine fled with her children to the German town of Goslar, where her parents, who owned local property there, were also staying. The Second World War in Europe ended on May 8, 1945.
Shortly after the war, Meinoud Rost van Tonningen died in prison, where he had been detained awaiting trial. He is said to have jumped over the stair balustrade. Florentine always disputed that her husband had committed suicide. According to her, he was murdered. She claimed the motive was that, as president of the Dutch Central Bank, he knew too much about black market financial dealings involving prominent individuals. In her book, she even accused Prince Bernhard, husband of Queen Juliana, of bearing the main responsibility for her husband's death.
In July 1948, Florentine returned to the Netherlands. She was immediately arrested 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.
She maintained lifelong contacts with many prominent ex-Nazis and Nazi sympathizers, such as Gudrun Himmler, the daughter of Heinrich Himmler, and Paula Hitler, the younger sister of Adolf Hitler. During the 1950s and 1960s, Florentine 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, Florentine became more politically active. Her villa in Velp became a meeting place for old and new far-right supporters. Solstice celebrations held in the style of the Third Reich became particularly notorious, earning her the nickname she had carried for decades: the Black Widow.
In the early 1980s, a small circle of loyal followers formed around her and established the Consortium de Levensboom, aimed at promoting and reviving Germanic culture. It published a periodical, Manuskripte, openly advocating National Socialism. At its peak, it had a circulation of 450 copies.
During the same period, she was indirectly involved in the founding of the Center Party, helping to collect signatures for the 1982 elections. To finance these activities, she used funds from her business, which ultimately led to bankruptcy.
Florentine was almost continuously involved in legal proceedings. In 1986, a major public debate arose over her continued receipt of a widow's pension. A parliamentary vote ultimately decided that no special legislation was needed for this exceptional case, allowing her to keep it. Her children always distanced themselves from her National Socialist ideology.
Florentine Rost van Tonningen was 92 years old when she died on March 24, 2007, in the Belgian town of Wassenberg, where she had spent her final years after being unable to find rental housing in the Netherlands. She later claimed that her life there had become impossible.
To prevent an influx of neo-fascists, she was buried quietly in the Dutch town of Rheden, where she had purchased a grave in the 1990s. She left behind debts, and there was no money for her funeral.