On Tuesday, Spain’s future queen Princess Leonor celebrated her 18th birthday—and sealed her claim to the throne—with a swearing-in ceremony at the nation’s parliament building, Palacio de las Cortes. In a white pantsuit á la Kate Middleton, she solemnly swore allegiance to the country’s constitution, which has been in effect since Spain transitioned to democracy in the 1970s.
In a speech, she discussed the importance of the constitution and mentioned that she has sworn allegiance to her father, King Félipe VI. “I have also taken an oath of fidelity to the King,” she said. “Not only to his person, but also to what the Crown symbolizes and represents: the unity and permanence of Spain.”
The princess, who is also known as the Princess of the Asturias, shared a piece of advice he gave her when she became a member of the Order of the Golden Fleece in 2018. “I remember very well what my father, the King, told me when he awarded me the Golden Fleece: ‘Let the constitution guide you continually. Fulfilling it and observing it, you will serve Spain with the humility and awareness of your institutional position.”’ she said. “They are words that I will keep in mind at all times.”
Outside of the parliament, enthusiasm for the princess was more energetic, and the streets surrounding the Palacio de las Cortes were filled with well-wishers waving the nation’s red and yellow flag. For years, the princess kept a low public profile, but the first rumblings of what the Spanish media has called “Leonormania” started in 2019, when she made her first formal speech at the Princess of Asturias Award for the Arts ceremony. Over the summer, she returned from two years at United World College of the Atlantic and began three years of military training, where her classmates simply call her Cadet Borbón Ortiz.
On October 12, she made another high-profile appearance at Spain’s national day celebrations in uniform and participated in a “jura de bandera” ceremony alongside her fellow cadets. She made headlines later that day, when two of her military classmates approached to shake her hand during a formal event. According to EuroNews, one cadet said, “How beautiful you look, Borbón” to the princess, causing her to smile shyly and her father and mother, Queen Letizia, to both laugh.
Now the mania has only intensified, and on Monday, the outlet called her the most charismatic royal. In a poll commissioned by the center-right newspaper El Mundo , 63% of the population said they believe that Leonor will make a good head of state when she ascends the throne.
At the end of her Tuesday speech, she took a cue from the late Queen Elizabeth and promised to live her life in service to the country. “From today I owe myself to all Spanish people, whom I will serve at all times with respect and loyalty. There is no greater pride,” she said. “On this important day—which I will always remember with emotion—I ask you to trust me, as I have placed all my trust in our future, in the future of Spain.”
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