Future Queen of Spain Princess Leonor Rings in 18th Birthday with Tradition — and a Symbolic New Necklace

The Princess of Asturias took an oath to obey the constitution — just like her father, King Felipe, did when he came of age

Princess Leonor of Spain is taking the next step to the throne.

The future queen turned 18 on Tuesday and marked the milestone by swearing allegiance to the Spanish Constitution. Accompanied by her parents, King Felipe and Queen Letizia, and 16-year-old sister, Princess Sofia, to the Congress of Deputies in Madrid, Princess Leonor pledged her loyalty to her country before the Cortes Generales (the Spanish parliament) as she came of age.

"I swear to faithfully carry out my duties, to keep and ensure that the Constitution and the laws are kept, to respect the rights of citizens and the Autonomous Communities, as well as loyalty to the King,” Leonor said during the solemn ceremony in the Chamber, per the Spanish royal court.

Francina Armengol, president of Cortes Generales, accepted her oath and replied, “The Cortes Generales have just received the oath that Your Highness has taken, in compliance with the Constitution, as heir to the Crown. Ladies and gentlemen. Long live the Constitution! Long live the King! Long live Spain!”

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The Princess of Asturias continued an important tradition as she reached the age of majority and followed in her father’s footsteps. According to the court, article 61.2 of the Spanish Constitution states that “The Crown Prince, upon reaching of age, and the Regent or Regents upon taking charge of their functions, will take the same oath, as well as that of fidelity to the King.”

King Felipe, 55, took the same pledge on his 18th birthday in 1986, and his eldest daughter can now act as regent in his absence, the Daily Mail reported.

The ceremony came to a patriotic close as the music unit of the Royal Guard played the national anthem and a 19-gun salute was fired on the esplanade of the Almudena Cathedral, where Felipe and Letizia married in 2004.

The Spanish royal family moved to the press desk, where Princess Leonor was presented with medals by the presidents of Congress and Senate, and she signed the second edition of the Book of Honor of the Congress of Deputies.

The royals took time to greet the government reps, officials and other guests invited to the event in the Hall of Lost Steps, before taking in the military parade outside. The procession featured units from all three Armies and the Civil Guard, a fitting tribute amid Princess Leonor’s three-year military training with the Army, Navy and Air Force.

Related: Spain's Future Queen Princess Leonor Starts 3-Year Military Training With Sweet Send-off From Family

Princess Leonor, her parents and sister then traveled to the Royal Palace of Madrid, where King Felipe presented his heir with the Collar of the Royal and Distinguished Spanish Order of Carlos III. The historic distinction is the highest order of chivalry in Spain, awarded to recognize exemplary service to the nation, and is comprised of five degrees: Collar, Grand Cross, Commendation of Number, Commendation and Cross.

According to the court, the Charles III Necklace is exclusive to members of the Spanish royal family and heads of state and government, plus citizens who have held the Grand Cross rank for at least three years. Only 25 living Spanish citizens (with the exclusion of the royal family) can receive the necklace at a time.

On accepting the honor, Princess Leonor reiterated her commitment to the Constitution and fidelity to the King. Her father also received the Collar of the Order of Charles III the year he turned 18.

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“From today I owe myself to all Spaniards, whom I will serve at all times with respect and loyalty. There is no greater pride. On this very important day — which I will always remember with emotion — I ask you to trust me, as I have put all my trust in our future, in the future of Spain,” the Princess of Asturias said. “I have solemnly, formally and publicly committed myself to our democratic principles and our constitutional values, which I fully assume. And I have assumed a great responsibility towards Spain before the Cortes Generales, which I hope to reciprocate with the greatest dignity and with the best example.”

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After the distinction was distributed, King Felipe and Queen Letizia, 51, hosted a lunch for over a hundred guests.

The day of the ceremony was especially significant as Princess Leonor will be Spain’s first queen regnant since Queen Isabella II (who reigned from 1833 to 1868) when she accedes one day. With it will come the royal responsibility of serving as supreme commander of the Spanish armed forces, and Leonor began her traditional military training at the General Military Academy of Zaragoza over the summer. The Princess of Asturias is training as a Lady Cadet for the 2023-2024 academic year, before moving to study with other branches.

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