LA BISBAL D’EMPORDÀ, Spain — The man serving the drinks at the pub is Albert Solà Jimenez, and he has quite a tale to tell.
It starts when he was an orphaned child, at first raised by peasants on a Mediterranean island, then whisked to a mansion in Barcelona. There were rumors of his “noble birth,” he says, whispered by generals and diplomats. Then came a Spanish secret agent who offered to connect the dots on his origins, he says.
The conclusion was the denouement of a fairy tale.
“It’s quite simple: I am the son of the king,” said Mr. Solà, as he carried two glasses of wine to customers in La Bisbal d’Empordà, a town of 10,000 inhabitants in the hills of Catalonia, the northeast corner of Spain’s border with France.
The colorful paternity claim is unverified by almost anyone’s standards. And Mr. Solà would not be the first royal pretender to spin a good yarn. Take Anna Anderson, for instance, who was known for years as the Grand Duchess Anastasia of Russia. She claimed that she alone escaped the Bolshevik firing squad that murdered her father, Czar Nicholas II, and the rest of her family.
Then again, Spain’s royal family had Leandro de Borbón, the love child of King Alfonso XIII and the Spanish actress Carmen Ruiz. He won the right to use the title “prince” after a bombshell memoir he published in 2002 called “The Royal Bastard.”
This all makes Mr. Solà’s claim one more headache for King Juan Carlos, Spain’s former monarch, who abdicated the throne in 2014 under a cloud of scandals. He vanished entirely for a short period last year, only to re-emerge in the United Arab Emirates amid investigations into his finances. He has been paying large sums in back taxes ever since.
Mr. Solà, for his part, has spent decades besieging the man he says is his father with handwritten letters to the royal residence, television interviews, a book laying out his claims, requests for royal DNA (not granted), a paternity lawsuit (dismissed) — and, of course, the tales he regales his customers with, where drinkers know him by the nickname “the little king.”
But is he really? At his home a short walk away sits a red box filled with documents related to the case, in which two clues stand out as critical.
One is a genetic test he took with Ingrid Sartiau, a Belgian woman who, like Mr. Solà, claims to be a child of Juan Carlos, though from a different mother. The test, verified as real by the Belgian lab that performed it, said Mr. Solà and Ms. Sartiau were most likely half siblings.
The second document is Mr. Solà’s birth certificate, showing he was born in 1956. Were Juan Carlos his father, it would make the countryside waiter the former monarch’s eldest son and, by extension, the man who — had his destiny been different — would be Spain’s king.
“It’s a case that could bring trouble for the monarchy,” said Rebeca Quintáns, a Spanish author who wrote a biography of Juan Carlos.
In some ways, Mr. Solà’s case is as much about his own origins as it is about his country’s past.
He was one of an estimated 300,000 people who experts like Ms. Quintáns say were orphaned during Spain’s dictatorship, which ended in the 1970s. It was a time when children, born to parents as diverse as political opponents and unwed mothers, vanished into a labyrinthine adoption system. Spain is now considering overhauls that would make it easier for this generation of orphans to seek information on their parents.
“Albert’s case is feasible since in that time, when a woman became pregnant with an illegitimate child, you hid the children and gave them to other families,” said María José Esteso Poves, who wrote a popular book on Spain’s so-called stolen babies.
But at the pub El Drac, where Mr. Solà worked, the question has long been decided.
After Mr. Solà rushed back inside to leave an order with the cooks, the owner, Manuel Martínez, sidled up to a table to offer his view.
“For a small town like La Bisbal, this is something big,” he said. “That the waiter of El Drac is the legitimate king.”
A spokesman for the royal family did not respond to requests for comment for this article. (But as an unrecognized son, royal observers say, Mr. Solà would have little chance of claiming the throne under Spain’s Constitution.)
With his patrician nose and sunken eyes — to many, the spit and image of Juan Carlos himself — Mr. Solà said his own face was the easiest evidence of his parentage. But as early as his childhood, he said there were clues that he was different from other orphans.
There was his original name, for one, Alberto Fernando Augusto Bach Ramón, which people told him had an aristocratic air. Shortly after he was born, he was taken from Barcelona to the island of Ibiza — which lies off the Spanish coast in the Mediterranean — and given to a family to be raised on a rural farm.
Eulalia Marí, 90, whose now deceased mother cared for Mr. Solà in those years, said it was common to raise the illegitimate children of families from the mainland. But the case of Mr. Solà was different: Ms. Marí recalled her family was paid nearly double the normal amount for care, 300 pesetas per month, a large sum to them at the time.
In 1961, Mr. Solà says, he returned to Barcelona, where his first memories were of living in a large mansion with a garden and high walls. A teacher came during the day for lessons, and he recalls an older woman, who he believes was his grandmother, came to visit him and give him toys.
At age 8, Mr. Solà moved again, this time to the home of Salvador Solà, a farmer in the province of Girona, not far from the French border. The family was poor, but once again Mr. Solà got the sense others were looking after his welfare: After he learned to drive, he said that he mysteriously received an expensive motorcycle and a car, and that he was given preferential treatment during his obligatory military service in his 20s.
The experiences left Mr. Solà wanting answers. In 1982, he recalled visiting an office in Barcelona that held local adoption records. The director, he said, appeared reluctant to help him, but cryptically added: “This was the most complex adoption in the history of this center.”
By 1999, Mr. Solà was living in Mexico, where he said diplomats told him they thought he came from a powerful family. He eventually moved back to Spain and made a request in court to see his records. The judge in the case asked to see him.
The judge, Mr. Solà claimed, said he was the son of Juan Carlos, who by then was king.
“It was the checkmate to this story,” Mr. Solà said.
However, the judge, Jorge Maza, who has since retired, said in an interview that he never told Mr. Solà he was the king’s son, leaving Mr. Solà’s claim in question.
In 2007, Mr. Solà took his case directly to Juan Carlos, sending a letter by fax to Zarzuela Palace, the royal residence.
“Dear father,” began the handwritten letter.
To his surprise, he received a reply.
Mr. Solà’s letter “has been sent to His Majesty,” said the note, on the king’s letterhead signed by the royal head of protocol.
Mr. Solà said he was at first delighted and waited to hear from the king. But he never did. Mr. Solà continued to write, with an increasingly angered tone.
“Give me some answers and I will not bother you again,” he wrote in one of the letters. “My patience has run out.”
Around that time, and by chance, Mr. Solà met a man who identified himself as a Spanish intelligence agent who said he believed Mr. Solà’s version of events.
The man, who declined to be identified in this article because of his work, said his colleagues had once been shown a picture of Mr. Solà as a child playing with Juan Carlos’s mother.
Mr. Solà said he believed it was the woman he remembered from his childhood at the mansion.
All told, Mr. Solà says, the mystery of his parentage has changed little about his life.
He still works as a waiter, though he recently left El Drac for another pub nearby. The move prompted a local newspaper article and a new flood of customers seeking pictures with the “king’s son.”
“The whole world comes looking for me,” he said. “I don’t know if it’s my looks or my story, but they are convinced.”