(Reuters) – The Spanish government demanded Catalan separatist leader Carles Puigdemont be extradited to face sedition charges in Spain on Friday after he was detained by Italian police in Sardinia.

Below is a timeline of key events since separatist leaders held an independence referendum in Catalonia that had been banned by courts:

Sept. 6, 2017 – Puigdemont, Catalonia’s pro-independence head of regional government, announces an independence referendum on Oct. 1 after securing the support of the separatist-controlled regional assembly.

Oct. 1, 2017 – About 2.3 million people, around 43% of eligible voters, turn out for the referendum, which had not been authorised by the courts. Spanish police wield batons at crowds attempting to vote. Some 90% voted to break away from Spain, according to the Catalan government. Many of those opposed to independence boycotted the ballot.

Oct. 27, 2017 – A majority of Catalan lawmakers – 70 out of 135 – vote to recognise the result of the referendum and declare Catalonia an independent nation. In response, Madrid imposes direct rule in the region, dissolving the parliament and dismissing Puigdemont, who subsequently fled to Belgium.

Nov. 2, 2017 – A Spanish judge orders pre-trial detention of former Catalan deputy leader Oriol Junqueras and eight other former regional officials on charges of rebellion, sedition and misuse of public funds.

Dec. 21, 2017 – In regional elections called by Madrid, separatist parties jointly win a narrow majority in the Catalan parliament.

June 2, 2018 – Socialist Pedro Sanchez is sworn in as Spain’s prime minister after ousting his conservative predecessor in a confidence vote. Madrid’s seven-month direct rule over Catalonia ends the same day with a new regional government sworn in.

Feb. 12, 2019 – The Supreme Court trial of 12 separatist leaders begins in Madrid.

Sept. 23, 2019 – Spanish police arrest nine pro-independence activists on suspicion of planning acts of violence.

Oct. 14, 2019 – Spain’s Supreme Court sentences nine separatist leaders to prison terms of between nine and 13 years. The ruling triggers mass, sometimes violent, protests in the region.

Jan. 7, 2020 – In Madrid, Sanchez forms a minority leftist coalition government. Catalonia’s separatist, leftist ERC party plays a crucial role in enabling his new government, in exchange for talks on resolving the region’s political conflict.

Feb. 6, 2020 – Sanchez meets pro-independence regional leader Quim Torra to start wider negotiations with the region.

Feb. 14, 2021 – In a snap election, Catalan separatist parties strengthen their majority in the regional assembly.

May 24, 2021 – Left-wing separatist Pere Aragones, from the ERC party, becomes head of the regional government, promising to pursue a strategy of dialogue to win independence from Spain.

June 22, 2021 – The Spanish government pardons nine separatist leaders jailed for their role in the independence bid in a gesture it hopes will foster dialogue.

March 9, 2021 – The European Parliament strips Puigdemont of the immunity he had enjoyed as a member since 2019.

Sept. 15, 2021 – Spanish premier Sanchez and Catalonia’s leader Aragones start a new round of talks to improve ties, but say their positions on independence remain “very far apart”.

Sept. 23, 2021 – Puigdemont is detained by Italian police in Sardinia on a European arrest warrant issued by Spain.

(Reporting by Joan Faus, editing by Andrei Khalip and Timothy Heritage)

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