Scotland's First Minister Nicola Sturgeon has proposed holding an independence referendum in October 2023, with some politicians in Spain's Catalonia autonomous region saying it could spur them on their own quest for self-determination.
Ms Sturgeon said on Tuesday that her Scottish National Party (SNP) planned to hold a vote, asking the question: "Should Scotland be an independent country?"
She also sent a personal email to more than 100,000 SNP staff, which also said: "The referendum campaign starts here."
To legally hold a referendum, the Scottish Parliament would need authorisation from the United Kingdom's Supreme Court, which Ms Sturgeon has requested. Alternatively, UK Prime Minister Boris Johnson could authorise it himself under section 30 of the Scotland Act, which was used by David Cameron to allow Scotland's 2014 independence referendum.
Ms Sturgeon said the people of Scotland "must have the right to choose".
"It's then entirely up to the people of Scotland what that choice is," Ms Sturgeon said.
"But simply trying to block democracy, as unionist politicians are doing, simply because they fear the verdict of the Scottish people, is not democratic, it's not acceptable, and it's not sustainable."
"Scottish democracy cannot be a prisoner to Boris Johnson or any UK prime minister."
A spokesperson for Mr Johnson said the government will review Ms Sturgeon's proposal, but the focus for the UK should be on "building a stronger economy".
Who wants independence, and who doesn't?
Scotland has a divided population and it has been for centuries. Religion, independence and football, which are all strongly connected, all play a part in this divide.
Scots who want to remain in the UK - also called "unionists" - support the British Crown and want Scotland to remain part of the United Kingdom.
Within Scotland, the main opposition to the SNP and its quest for Scottish sovereignty is the Scottish Conservative Party, led by Douglas Ross.
He, like Mr Johnson, argues that the economy is the "real" priority for Scotland at the moment, not another referendum.
"Nicola Sturgeon is at it all over again. Her eye is off the ball once more," Mr Ross said.
"The real priorities of the people of Scotland are on the back burner.
"She will use government time and resources to further her plan to break up the country.
"We won't take part in a pretend poll."
Scots who want independence believe that Scotland is a minority nation dominated by the United Kingdom, and should govern in its own right.
Glasgow local Dom McCearney told SBS News the younger generation felt particularly disconnected from British politics.
"I think a lot of Scottish people, especially younger Scottish people, feel a disconnect from Westminster politics," Mr McCearney said.
"The Tories haven’t won a majority in Scotland in decades but we keep getting Tory governments forced upon us.
"There’s a feeling as well that Scotland is politically different, it leans a little more left than the average voter in the rest of the UK."
Rangers fans often display the Union Jack at matches in a show of support towards the Crown. Credit: Kirk O'Rourke/PA
While Scottish independence is not based on a question of religion, the country is notorious for its historic violence between its Catholic and Protestant populations.
This is no better witnessed than in the football rivalry between Glasgow's Celtic FC, who are traditionally associated with the Catholic Church, and Glasgow's Rangers FC, who are traditionally associated with the Protestant religion.
Rangers fans commonly sport the Union Jack to show their support for the Crown and unity with England.
What happened last time, and will this time be different?
In 2014, Scotland held an unsuccessful independence referendum with 55.3 per cent (2,001,926) voting against independence, answering "No", and 44.7 per cent voting for independence, answering "Yes".
But "Yes" voters -who often sport flags with the word "yes" - have continued to rally for independence since the referendum, particularly after the UK's exit from Europe (Brexit).
When the last referendum was held, the majority of Scots wanted to remain in the European Union (EU) and voting for independence would have potentially meant a Scottish exit from the bloc.
Some criticised the BBC for what they said was biased coverage of the independence movement and referendum, claiming the British media outlet encouraged fears around independence, particularly in the context of membership to the EU.
Two years later, Brexit happened. While the UK voted to leave the EU by 52 per cent to 48 per cent, Scotland voted to remain by 62 per cent to 38 per cent.
The SNP says if Scotland is successful in achieving independence, it will attempt to negotiate with the EU for the country to return to the bloc.
Supporters of the campaign group Yes for EU outside the Scottish Parliament at Holyrood in Edinburgh in a protest against Brexit. Credit: Andrew Milligan/PA
What's the link with Catalonia?
The Scottish independence movement and the movement in Catalonia share similarities in their strives for self-determination, albeit with some key differences. This includes the fact that the UK has previously allowed Scotland to vote, and Spain doesn't want to leave the EU.
At independence demonstrations in both countries, the Catalan independence flag often flies alongside the Scottish one, in a sign of solidarity.
Pro-Catalan independence demonstrators march through the west end of Edinburgh to the European Commission offices. Credit: Ken Jack/Corbis via Getty Images
Catalan independence rose in popularity after central Spanish courts in 2010 rejected the region's appeal to reform to its autonomy statute, which is the agreement of the division of power it shares with Madrid.
As Spain doesn't operate under a federal system, Catalonia wanted some powers on how it governs issues such as its language, taxes, and judiciary systems. Former Spanish prime minister José Luis Rodríguez Zapatero agreed to the reforms, but it was later ruled unconstitutional by Spain's Constitutional Court.
This ruling left many Catalans feeling like they were dominated by Spain's central courts, regardless of the government in power, and led to a regional coalition government, led by Carles Puigdemont, to hold a referendum on 1 October 2017.
Spain, at the time led by Mariano Rajoy, ruled the referendum illegal before it was held, and sent thousands of national police to prevent the vote from happening.
On the day of the vote, Spanish police raided schools where voting took place, and forcibly prevented civilians from voting. Human rights advocacy groups such as Amnesty International condemned their actions as examples of police brutality.
Catalan pro-independence protesters march during a demonstration in Barcelona. Source: AP / Emilio Morenatti/AP
Aleix Sarri, international officer for one of the forming coalition independence parties, Junts, told SBS News that Scotland's recent announcement would inspire the Catalan government to pursue another referendum as well.
"Scotland leads the way for a new self-determination wave in Europe and will show again that borders are better decided through the ballot box not wars, state treaties or marriages centuries ago," Mr Sarri said.
"Scotland will prove again a mirror for Catalonia's push for independence and Spain's repressive tactics.
"[Ms] Sturgeon will not face prison or exile for organising a referendum and this points out the democratic depth of the UK compared to Spain that puts the unity of the state above democracy and human rights."
Spain's Supreme Court sentenced nine Catalan politicians and social figures to between nine and 13 years in prison for their involvement in the referendum.
The imprisonment, based on crimes of "sedition" was condemned by organisations such as Amnesty International, the World Organisation Against Torture, and the International Association of Democratic Lawyers.
After the disallowed referendum, former leader of the Catalan government Carles Puigdemont fled Spain to Belgium, where he still lives in self-exile and continues to campaign for Catalan self-determination.
