George I lived from 28 May 1660 to 11 June 1727. He was the first monarch of the House of Hanover, and ruled as King of Great Britain and King of Ireland from 1 August 1714 until his death. George I also served as the Duke of Brunswick-Lüneburg (Hanover) and a Prince Elector of the Holy Roman Empire. The wider picture in Scotland at the time is set out in our Historical Timeline.
Until the age of 41, the possibility of George becoming King of Great Britain probably never occurred to him. However, in 1701 the English Parliament passed the Act of Settlement. This confirmed Queen Anne as heir to the throne after King William. And if neither of them had legitimate offspring, after Anne the throne would then go to the Protestant Sophia, Electress of Hanover, who was a grand-daughter of James VI/I and whose mother had been sister to Charles II and James VII/II. The specific aim of the Act of Settlement was to exclude from the succession any Catholic descendants of James VII/II, especially his son, James Francis Edward Stuart.
The Electress Sophia of Hanover died in June 1714, and six weeks later on 1 August 1714 Anne died: with the result that George I became King of Great Britain. George arrived in England on 18 September 1714; and was crowned at Westminster Abbey on 20 October 1714. Barely able to speak any English, and keen to make regular visits to Hanover, George was a very unpopular king. This was not helped when it became known that he kept his ex-wife and first cousin, the Princess Sophia of Celle, prisoner in a German Castle, where she would remain for life. Public opinion would probably have been still more anti-George had it been known at the time that, in 1694, he had paid a courtier a vast sum of money to murder Sophia's lover, the Swedish Count, Philip Christoph von Königsmarck, and dispose of his body in a river. On the brighter side, George and Sophie's marriage had produced an heir, George, born in 1687, before it went into terminal decline.
George's unpopularity came to a head with "The Fifteen", the Jacobite uprising of 1715. George had snubbed one of Queen Anne's senior Ministers, John Erskine, 23rd Earl of Mar. Mar returned to Scotland, and on 6 September 1715 raised a standard at Braemar for the Old Pretender, "James VIII". Given George's unpopularity and the rising tide of support across Britain for the Jacobites, the conditions were ideal for a successful "regime change" of the sort that had taken place during the Glorious Revolution. But Mar had failed to tell the Old Pretender what he was planning; he failed to coordinate his uprisings with Jacobite uprisings at the same time in England; and he proved a very poor general. Indeed, Mar's conduct of the 1715 Uprising was so inept it has sometimes been suggested he was actually working on behalf of the Hanoverians. Whatever the truth of that, by the time the Old Pretender landed in Peterhead in December 1715, the uprising was already fizzling out.
On the continent, George was instrumental in forming alliances against Spain in the continuing conflicts that followed the War of the Spanish Succession. This was doubtless one of the factors that led to an attempt by the Spanish in 1719 to land an army in England to put the Old Pretender on the throne. The invasion failed because of bad weather, though a diversionary attack by two ships and 300 Spanish troops in western Scotland went ahead, only to be defeated by government forces at the Battle of Glen Shiel.
In England, George became, if possible, still more unpopular because of The South Sea Bubble. This was an investment scandal involving Government bonds that led to many individuals losing their fortunes. In the aftermath, Sir Robert Walpole came to prominence as the first - albeit unofficial - Prime Minister. George soon became heavily reliant on Walpole, allowing the latter to accumulate considerable power, often through bribery of Members of Parliament, and become even more wealth, largely though the widespread sale of Honours.
George I had become King of Great Britain at the age of 54. He was to rule for just 13 years before dying of a stroke in Osnabruck while on a visit to Hanover, on 11 June 1727. He was succeeded by George II with whom he had a very poor relationship for a number of years. As Prince of Wales, George II had publicly undermined his father's policies on a number of occasions, and the two had even had a stand-up fight over who should be named as godparents at the christening in 1717 of the one of the younger George's children.