In 1941, during the Second World War, Prince Paul was forcibly removed from power after signing the Tripartite Pact, which took Yugoslavia into the Axis with Germany and Italy.

[2] She grew up alongside her parents and younger sisters, Princesses Elizabeth (1904–1955) and Marina (1906–1968), at the Nicholas Palace, the current seat of the Italian Embassy in Athens.

After the fallout between King Constantine I and his prime minister Eleftherios Venizelos over whether Greece should enter the conflict, a virtual civil war shook the Hellenic kingdom, which was partially occupied by the Allies from 1915.

[5] Finally, on 10 June 1917, King Constantine was forced to leave power by the ultimatum of the French High Commissioner Charles Jonnart and he went into exile with his wife and children in German-speaking Switzerland.

[N 2][6][7] Described as the "evil genius behind the monarchy" by the Venizelists, Prince Nicolas was quickly forced to leave Athens in turn and join his brother abroad.

[9] The restoration of Constantine I in 1920 allowed Olga to return to her native country for a brief period, but the king's final abdication in 1922 forced the young princess and her relatives to resume their life in exile.

[10][11] Considered, along with her sister Marina, to be "one of the most beautiful young women of her time",[12][13] Princess Olga had, according to biographer Ricardo Mateos Sainz de Medrano, a "discreet, romantic and fragile personality".

[15] However, the awkwardness of the Danish prince, who held the hand of one of Olga's sisters instead of hers during the official presentation of the young couple to the Athenian crowd, lastingly humiliated the future bride.

With him, she made several official stays abroad and notably met the dictators Benito Mussolini and Adolf Hitler in Rome and Berlin in April and June 1939, respectively.

She stayed in Athens to witness the final days of her father, Prince Nicolas, and to take care of her mother, the Grand Duchess Elena Vladimirovna.

[29] Paul, Olga and their three children were then arrested and handed over to the British, who deported them to Greece (where they were welcomed by King George II[30]) then to Egypt (under the pretext of intrigue[31]).

Settled far from Nairobi, in Oserian, in the region of Lake Naivasha, they took up residence in the country house of the late Lord Erroll, where they would be watched by the former governor of the colony.

[33] Condemned to inactivity, Olga therefore devoted her days to maintaining the residence, learning to cook and supervising the education of her children, while her husband sank into melancholy and depression.

[36] In September 1942, the death of Prince George, Duke of Kent, in an air crash left his wife, Princess Marina, inconsolable and the British government had to allow Olga to stay in the United Kingdom to keep her sister's company.

[44] In 1948, Paul, Olga and their three children were finally granted permission to leave South Africa, but Yugoslavia had adopted a communist regime in 1945 and they could not return to their country.

In Tuscany, Olga had the pleasure of reuniting with her cousin and friend Helen, Queen Mother of Romania, while in the United Kingdom she was always welcomed by her sister Marina, Duchess of Kent, and the rest of the British royal family.

[47] At the wedding of the Yugoslav pretender, it was also Princess Olga who accompanied him to the altar, as the prince's mother and grandmother were not able to attend the ceremony due to health issues.

The children and grandchildren of the couple, as well as Crown Prince Alexander and his wife Princess Katherine, and Serbian President Tomislav Nikolić and his government participated in the event.