On 18 September 2014, voters in Scotland visited the polls to vote in a historic referendum. In the voting booth, they were asked “Should Scotland be an independent country?”

The vote was brought about by the victory of the Scottish National Party, a party that had campaigned for a referendum on Scottish independence since devolution. The party formed a minority government in 2007, and unable to pass legislation to hold a referendum, introduced the National Conversations which were designed to explore options for Scotland’s constitutional future. In 2011, the party formed the majority at Holyrood and was able to pursue its independence ambitions.

However, the Scottish Parliament did not have the power to hold a binding constitutional referendum. Constitutional matters are reserved powers, held at Westminster. The UK Government agreed that the election result provided the Scottish Government a mandate to hold a referendum, and to enable this, the Scottish and UK Governments engaged in negotiations over the conditions in which a vote would be held. The Edinburgh Agreement, signed by then Prime Minister David Cameron and First Minister Alex Salmond, was the result.

The Edinburgh Agreement set out the key terms of the referendum. The referendum was to: have a clear legal base, be legislated for by the Scottish Parliament; to be conducted so as to command the confidence of parliaments, government, and people, and deliver a fair test and decisive expression.

Once the agreement was signed, a Section 30 order was issued, which allowed a constitutionally binding referendum to be organised. The legislation setting out the question, franchise, and terms of the campaign was passed by Holyrood in 2013.

Over the subsequent months, the campaigns formed. The official organisation of the yes side was Yes Scotland, bringing together the Scottish National Party and the Scottish Greens. Representatives of Labour, Conservatives, and the Liberal Democrats formed Better Together, to campaign against the referendum. The campaign centred on a few key themes, including the economy and currency of an independent Scotland, Scotland’s place within the European Union, and the potential of an independent Scotland to deliver on social and policy objectives.

Over the campaign, the polling narrowed, with support for independence growing. A poll the week before the vote suggested a narrow victory for yes. In response, the leaders of the Conservative, Labour, and Liberal Democrat parties pledged in a statement widely known as ‘The Vow’ to make the Scottish Parliament a permanent institution, retain the Barnett Formula, and deliver “extensive new powers” for Scotland.

45% of voters opted for independence, while 55% rejected the proposition. However, the question of Scottish independence remains a live one.