Before his elevation to king of England, George had already led an eventful life. He was the eldest child with five brothers and a sister. He outlived them all except his youngest brother Ernst. He had been a handsome youth, and still retained something of a cherubic if fat face, though his seeming inability to smile made him appear surly. He was not tall, but was fit and athletic, though he later became rather stout. He was well educated but delighted most in riding, hunting and military exercise. He first saw military service in 1675, and was involved in the Dutch and Turkish wars, distinguishing himself at Neerwinden in 1693. He developed a good relationship with John Churchill, the future duke of Marlborough, during the War of the Spanish Succession and commanded the Imperial Army on the Upper Rhine from 1707 to 1709. He was elevated to the College of Electors of the Empire in 1708 and became arch-treasurer of the Empire in 1710. He was resourceful and much respected, but was also highly ambitious, vindictive and used to having his own way. He had already demonstrated this by his treatment of his wife, which had become something of a scandal in Europe. He had married the beautiful sixteen year-old Sophia Dorothea of Celle in 1682. The marriage was at first happy and they had two children: George Augustus and Sophia Dorothea. Sophia soon tired of her boorish husband, however, who seemed to have little respect for women, and she began an affair with Philip von Konigsmark, a Swedish colonel of dragoons. When George discovered this in July 1694 he was furious. Sophia was imprisoned in the Castle of Ahlden for the rest of her life, forbidden to remarry and denied access to her children. Divorce proceedings were concluded in December 1694. Konigsmark disappeared and it was widely believed that George had ordered his death. His body was supposed to have been discovered years later buried under the floorboards at the elector's palace. However, Konigsmark had earlier had an affair with Clara, the Countess von Platten, and it was believed that she may have lured the Colonel to his death. This becomes even more sordid when we learn that Clara had also been the mistress of George's father, Ernst, and had borne him at least four children, one of whom, Sophia Charlotte, was rumoured to be George's mistress, even though she was his half-sister. It is more likely that the two simply enjoyed each other's company. Sophia Charlotte was not an attractive lady; in fact she grew to be excessively corpulent, so that when she and the king were seen together they were nick-named the Elephant and Castle. She became a naturalised British subject and was raised to the peerage as baroness of Brentford and countess of Darlington in 1722. George's one public mistress was Ehrengard Melusine von Schulenburg, an extremely thin lady whom the Germans called "the scarecrow" and the British dubbed "the Maypole". There is a strong belief that George may have subsequently married Melusine in secret, especially as in later years she was created Princess von Eberstein by the Emperor Charles VI who would not have done so had she not had some royal status. Robert Walpole also regarded her "as much queen of England as anyone ever was." She was generally known by the title duchess of Kendal, which she was given in March 1719. George had already had two children by her before he divorced his wife, which only emphasises his hypocritical attitude when he discovered her affair. England's Queen Anne had taken a dislike to George when he visited her as far back as 1680 pursuing a possible marriage alliance, and from his subsequent sexual adventures one can only imagine what the outcome might have been for Anne and England had they married.

The English and Scots did not warm to George either when he paraded through London in September 1714. He had already taken nearly eight weeks to come to Britain, revelling in his new found glory in a series of parties across Europe. He was jeered by Londoners, who never quite took him seriously. By this time the power of the king was waning against the growing power of Parliament and, while the authority of the king retained a certain mystical aura, this was not what it had been before the Civil War and the English were already starting to regard the monarch as a figurehead. While they had taken Mary and Anne to their hearts, they did not like these foreigners who kept turning up to claim the throne - first William of Orange and then George of Hanover. This seriously damaged the acceptability of the monarchy in the eyes of the public. The Scots liked this "wee German laddie" even less. The Jacobite supporters of James 11 and his son James Edward Stuart grew in strength and in September 1715 the first Jacobite rebellion erupted at Braemar. It could have been far more serious than it was if the Old Pretender had not turned out to be such a discouraging pessimist. The rebellion fizzled out, but George still exacted a vicious penalty upon those who had taken part.

Despite what his amorous adventures might suggest (in fact they probably support it), George was shy and tended to keep out of the limelight when he could. He was not one for intellectual pursuits, though he did have a love for music and it was through George that the composer George Frederic Handel came to England. His Water Music was composed for a royal water-party on 22 August 1715, and George's love of Handel's work led to the foundation of the first Royal Academy of Music in 1720. George's shyness and inability to communicate well in English made him all the more blunt and short-tempered. He had been used to getting his own way in Hanover and could not adapt to the English parliamentary system where he needed to seek approval for his actions, especially when this affected his foreign policy and his wish to protect Hanover's interests. Because of the language problems, especially after the rift with his son in 1717 which meant the younger George no longer attended cabinet meetings to help translate, George needed another minister to represent him. This was the start of the post of Prime Minister, but it also reduced George's direct sphere of control. George had previously allied himself with Peter the Great of Russia and was keen to ensure that he benefitted from Peter's war with Sweden. To do so he needed to have control over his foreign policy and he could not do this with the Whig government that had come to power under Robert Walpole in 1715 after the failure of the Jacobite rebellion. In 1716 the Septennial Act had been passed, which postponed the opportunity of the Tories to return to power for four years. George distrusted the strong-minded and exceedingly able Walpole who would not sanction the funds George needed for his new campaign against Russia. George, however, rapidly appreciated that he could influence who led the Whigs. George set one faction against another within the party and succeeded in aiding the weak and malleable earl of Sunderland and Lord Stanhope to oust Walpole in 1717. George was now able to dictate his terms to Stanhope and gain an alliance with Holland and France against Russia. However in opposing Walpole he made a dangerous enemy. Walpole allied himself with George's son, George Augustus (later George II), who served as regent on his father's many forays back to Hanover. George despised his father because of his treatment of his mother, and would have been only too happy to depose him. He established a clique, known as the Leicester House Set, with the sole intention of frustrating the king's plans, and Walpole became part of the group. Walpole also became friends with Prince George's wife, Caroline, princess of Wales, an intelligent and influential lady who gave Walpole her stolid support. King George soon realised that he could not prevail against such opposition and was forced to be reconciled with Walpole. This was precipitated by the economic disaster known as the South Sea Bubble. The South Sea Company had been established in 1711, trading with the Spanish colonies in South America in anticipation of benefits that would arise from success in the War of the Spanish Succession. King George was made governor of the company in 1718 and it became fashionable to invest, especially once the Company took over the management of the National Debt in 1720. Senior officials in the company began to issue false stock to meet the demand and in September 1720 this bubble burst. Thousands of speculators found that their investment was worthless, including most of the country's leading nobility. When it was found that cabinet ministers and court officials had been involved in the dirty dealings it became a national scandal, threatening the Hanoverian dynasty. George was forced to rely on Walpole's skill in resolving the affair and restoring order. From then on Walpole was in supreme power and dominated English affairs. George's relationship with his politicians and the general state of English religious and cultural society at this time was lampooned by Jonathan Swift in Gulliver's Travels (1726).

Because of the supremacy of Parliament, George removed himself further from public affairs. It made the king less of a target, although the jacobites still wished to restore the Stuart Pretender. In 1722 a plot was uncovered to do just that, known as the Atterbury Plot after one of its leading conspirators Francis Atterbury, bishop of Rochester. Where once he would have been executed, Atterbury was imprisoned and then banished, and all his possessions confiscated. Generally, though, plots against the king diminished because Walpole had him under control. George's excesses were by and large eradicated, although the relationship with Spain remained poor, resulting in a dispute over Gibraltar and a fruitless expedition against Spain's American colonies.