For many centuries, Scotland existed as an independent kingdom until, at the start of the 17th century, the crowns of Scotland and England were united.
Then, a little over a century later, in 1707, the two countries formed a political union, creating the Kingdom of Great Britain. Despite this, Scotland retained many distinct elements of identity, including its own legal system.
In the late 1990s, Scotland was granted a greater degree of autonomy and a Scottish Parliament was re-established. This in turn led to increasing calls for independence.
In September 2014, following an agreement with the British Government, a referendum was held. By 55.3% to 44.7% on an 84.6% turnout, voters chose to remain in the Union.
Although many thought that this would settle the matter for a generation, calls for independence have continued. This has largely been driven by the 2016 referendum on leaving the European Union.
While Scotland voted overwhelmingly to remain in the EU, the “leave” vote in the far more populous England won. Scotland also argues that its voice has been ignored in the subsequent Brexit negotiations.
As a result, the Scottish Government has announced its intention to hold another independence referendum in 2021. However, the British Government insisted it won’t permit another referendum within the lifetime of the current British Parliament, which is expected to run until 2024.
This obviously paves the way for what could be a very serious constitutional showdown.