Spain's King Felipe VI begins a new reign Thursday already facing a threat to the unity of his kingdom as the northeastern region of Catalonia fights to hold an independence referendum on November 9.
With only a ceremonial role in Spain's parliamentary democracy, the new king, a tall 46-year-old former Olympic yachtsman, has limited capacity to mend all the woes of a country suffering high unemployment and longstanding separatist tensions.
Yet political analysts say he can help to soothe the bruised nationalist sentiments of the northern regions of Catalonia and the Basque Country, not least by fostering a dialogue with Madrid that is judged by many to be lacking.
In a speech on June 3, the day after his father Juan Carlos revealed he was abdicating, the future king gave a sign that he understood the scale of the challenge as secessionists in Catalonia, in particular, seek to redraw the map of Spain.
Felipe spoke of Spain as a "united and diverse" nation.
"Only by uniting our desires, putting the common good ahead of individual interests and promoting the initiative, curiosity and creativity of each person, can we manage to advance to better scenarios," he said.
Felipe's speech was "an outstretched hand" to Spanish regions that have a distinct culture, said constitutional law professor Antonio Torres del Moral at the respected distance-learning university UNED.
On his deathbed, General Francisco Franco, who centralised power in Madrid, told Juan Carlos: "The only thing I ask of you, your highness, is that you preserve the unity of Spain."
Under the 1978 constitution that ushered in Spain's democracy after Franco's death in 1975, the 17 regions were given broad autonomy.
Each region has its own education and health budget, government and parliament, court system, and in some cases police force. Catalonia, the Basque Country and Galicia speak their own languages.
During its transition from dictatorship to democracy, Spain chose a "coffee for everyone" model in which each region had largely similar rights, rejecting an alternative "cheeseboard" proposal in which each region would have selected its preferred model, said Torres del Moral.
Now, however, there is pressure for wider regional differences to be recognised, he said.
"We need to rethink the 'coffee for everyone' model and start helping ourselves to the cheeseboard," the academic said.
The Spanish constitution cites the "indissoluble unity of the Spanish nation" while guaranteeing the right to self-government of its "nationalities and regions".
Yet Spain's Constitutional Court ruled in 2010 that Catalonia's revamped statute of autonomy, approved in a popular referendum, had to scrap references to Catalonia as a "nation".
The ruling fired up nationalist sentiment in Catalonia.
Then, Catalan political leader Artur Mas, accusing Madrid of imposing an unfair tax burden on Catalonia at a time of economic crisis, promised to hold an independence referendum.
Hundreds of thousands of Catalans poured into the streets last September to demand a vote on independence from Spain.
Prime Minister Mariano Rajoy vowed to block any such move, insisting it would flout the Spanish constitution.
In the Basque Country, too, however, there are signs of a similar separatist sentiment albeit on a smaller scale. Organisers said some 100,000 people joined hands in a June 8 demonstration there to demand self-rule.
It is unclear what role Felipe could play.
"The monarchs, even though they can't strictly enter into politics, have some room to manoeuvre," said Fermin Bouza, a sociology lecturer at Madrid's Complutense University.
Felipe would be in an "ideal position" to encourage politicians to sit down and talk, he said.
"The Catalan question is one in which there has been a minimal dialogue," the academic said, describing Rajoy as a man of few words who had done little more than recite tracts from the Spanish constitution.
"However much you quote the constitution, the problem persists and every day it becomes more divisive," the sociologist said.
The Spanish system of regional government is "worn out", concluded Ignacio Escolar, head of the online publication eldiario.es.
"It is incapable of coping with this country of nations and regions of which the constitution speaks," he wrote.