Fueled by economic grievances and a distinct language and culture, aspirations for an independent state in Catalonia have ebbed and flowed for generations.
But the current confrontation has presented a vexing quandary not only for Spain but the entire European Union, pitting democratic rights and demands for self-determination against the desire to preserve the sovereignty and territorial integrity of an important member state.
Mr. Rajoy took the bold steps with broad support from Spainâs main political opposition, and will almost certainly receive the required approval next week from the Spanish Senate, where his own conservative party holds a majority.
He did so despite repeated appeals for dialogue and mediation by the Catalan leader, Carles Puigdemont, whose independence drive has been shunned by wary European Union officials.
Mr. Rajoy said the Catalan government had never offered real dialogue but had instead tried to impose its secessionist project on Catalan citizens and the rest of the country in violation of Spainâs Constitution.
He said his government was putting an end to âa unilateral process, contrary to the law and searching for confrontationâ because âno government of any democratic country can accept that the law be violated, ignored and changed.â
Mr. Rajoy said he planned to remove Mr. Puigdemont, and the rest of his separatist administration from office. The central government was also poised to take charge of Cataloniaâs autonomous police force and the Catalan center for telecommunications.
Mr. Rajoy did not ask to dissolve the Catalan Parliament, but instead said that the president of the assembly would not be allowed to take any initiative judged to be contrary to Spainâs Constitution for a period of 30 days, including trying to propose another leader to replace Mr. Puigdemont.
Mr. Rajoy said that his goal was to arrange new Catalan elections within six months, so as to lift the measures taken under Article 155 as soon as possible.
Itâs unclear, however, how such elections would be organized or whether they would significantly change Cataloniaâs political landscape, let alone help to resolve the territorial conflict.
Mr. Puigdemont led a mass demonstration in Barcelona, the regionâs capital, on Saturday afternoon, before giving his official response to Mr. Rajoyâs decision.
Several Catalan separatist politicians, however, reacted immediately to Mr. Rajoyâs announcement, warning that it would escalate rather than resolve the conflict.
Josep LluÃs Cleries, a Catalan Senator, told reporters on Saturday that Mr. Rajoyâs decision showed that âthe Spain of today is not democratic because what he has said is a return to the year 1975,â referring to Francoâs death. Mr. Rajoy, he added, was suspending not autonomy in Catalonia but democracy.