Pro-independence protesters are expected to flood the streets of Barcelona Wednesday for Catalonia's national day, three weeks ahead of an October 1 secession referendum banned by Spain.

Here are the key dates in the recent history of the wealthy Spanish region's independence drive.

- 2006 -

March 30: Spain's parliament approves a new autonomy charter for Catalonia that increases the region's fiscal and judicial powers and describes it as a "nation".

July 31: Prime Minister Mariano Rajoy's conservative Popular Party (PP), which has only marginal support in Catalonia, appeals the autonomy charter, accusing it of "privileging" Catalonia.

- 2010 -

June 28: Spain's Constitutional Court strikes down parts of the 2006 autonomy charter in response to the PP's appeal. It rules that the word "nation" to describe the region has "no legal value" and rejects the "preferential" use of the Catalan language in municipal services.

July 10: Hundreds of thousands of people protest in Barcelona, the capital of Catalonia, against the court ruling amid chants of "We are a nation, we decide".

- 2012 -

September 11: At the height of Spain's economic crisis, more than a million people protest in Barcelona demanding independence for Catalonia.

Major demonstrations are held in following years on the same date, marking Catalonia's national day.

September 20: Prime Minister Mariano Rajoy rejects Catalan President Artur Mas's call for greater tax-and-spend powers for the region. Five days later, Mas calls a snap regional election promising to hold a referendum on Catalonia's future.

November 26: Mas's centre-right CiU alliance wins the snap election overall but fails to secure an absolute majority in the regional parliament.

- 2013 -

September 11: Hundreds of thousands of Catalans join hands to form a human chain stretching more than 400 kilometres (250 miles) across the Mediterranean coast to push for independence.

- 2014 -

November 9: Catalonia defies Madrid and presses ahead with a symbolic vote on independence. Turnout is just 37 percent, but more than 80 percent -- 1.8 million people -- vote in favour of independence.

- 2015 -

September 27: The pro-independence Together For Yes alliance secures 62 seats in the regional assembly and the radical leftwing separatist group CUP wins 10, giving them an absolute majority.

But the separatist block falls short of winning a majority of votes in the election, which is portrayed as a proxy vote on independence, capturing just 47.8 percent of the ballot.

November 9: All 72 pro-independence lawmakers in the Catalan parliament -- the majority -- vote for a resolution that kicks off the process to secede from Spain. The country's Constitutional Court will later strike it down.

- 2016 -

January 10: Longtime separatist Carles Puigdemont becomes president of Catalonia.

- 2017 -

June 9: Puigdemont announces a referendum on independence to be held in Catalonia on October 1 with the following question posed to voters: "Do you want Catalonia to be an independent country in the form of a republic?" Spain's central government says it will block the referendum.

July 3: Puigdemont dismisses a member of his regional government who had raised doubts about the viability of the referendum. Three other members of his government whose support for the vote was in doubt also step down, as does the head of the regional Catalan police.

Rajoy accuses the Catalan government of harbouring "authoritarian delusions".

September 6: Catalonia's regional parliament approves a law allowing the referendum and the regional government signs a decree officially calling the vote.

September 8: Spain's Constitutional Court temporarily suspends the referendum following a legal challenge from Madrid but the Catalan government vows to go ahead with it.

Source: AFP