Scotland Is About To Vote On Whether To Leave The UK — Here's Everything You Need To Know
Scotland Flag
Scotland Flag

AP Photo / Chris Clark

Scotland's referendum on independence, a vote that could break up the United Kingdom, will take place on Thursday.

Scotland will vote whether to become an independent nation, potentially severing a 307-year-old union with England, on Thursday. (See our live coverage of the voting here.) Here's what you need to know.

When did Scotland and England unite?

The Act of Union between Scotland and England was signed on Jan. 16, 1707. It came into effect on May 1 of that year, creating the United Kingdom of Britain. The Scottish Parliament was dissolved, and a single Parliament was created at Westminster in London.

Why did Scotland and England join in the first place?

Scotland and England have a complicated history, but the short answer is that Scotland needed an economic boost. The country's finances were a mess after a failed attempt to establish a trading colony in Panama. This unsuccessful scheme "was conclusive evidence that Scotland's future prosperity was best served by union," The Guardian writes.

What are the opposing sides in the referendum?

There are two groups: The Yes campaign is in favor of independence. The official name for this campaign is Yes Scotland. The No campaign wants to keep the Union intact. The official name of this campaign is Better Together.

Who are the campaign leaders?

Alistair Darling/Alex Salmond
Alistair Darling/Alex Salmond

AP Photo/Sang Tan, Frank Augstein A combination photo of Labour Party MP Alistair Darling and Scotland's First Minister Alex Salmond.

Alex Salmond is leading the Yes Scotland campaign, which supports independence. He is currently the leader of the Scottish National Party (SNP).

Alistair Darling is leading the Better Together campaign, which supports staying with the UK. He was the British Chancellor from 2007 to 2010.

When is the referendum?

Thursday, Sept. 18.

What will the ballot say?

There is just one question: "Should Scotland be an independent country?" Voters will tick one box: Yes or No.

When did Scotland get the power to hold a referendum?

Edinburgh Agreement
Edinburgh Agreement

AP Photo/Gordon Terris, Pool

The referendum agreement signed by Prime Minister David Cameron, Scotland First Minister Alex Salmond, Scottish Secretary Michael Moore, and Deputy First Minister Nicola Sturgeon during a meeting at St Andrews House in Edinburgh on Oct. 15, 2012.

David Cameron signed an agreement in October 2012 ensuring that the Scottish parliament, known as Holyrood, could hold a referendum on independence. This is called the Edinburgh Agreement. This followed a majority win by the Scottish National Party in the 2011 parliamentary elections, indicating a growing desire for independence.