After Peterloo and the Cato Street Conspiracy, in both of which the outbreak of substantial violence, either by the state or against it, seemed to threaten political opposition in the country suddenly coalesced around the cause of Queen Caroline, the wife of the Prince Regent, who had been estranged from him more or less from the moment she had given birth to their daughter Princess Charlotte (one of the few popular members of the royal family, who died in childbirth in 1817). Rumours surrounding Caroline's conduct abroad were widespread, fueled by the Regent and his allies. An investigation had been conducted in anticipation of divorce proceedings in 1806, but while the inquiry censured her for 'levity of conduct', the Cabinet agreed not to exclude her from court. A further fishing expedition in Italy was conducted in 1816, producing the widely caricatured and notorious 'Green Bag' of evidence to be used against her. On the death of George III in January 1820, and with the prospect of Caroline attending the coronation, an attempt was made to buy her off (for £50,000) and get her to repudiate her title. This failed, and she declared she would return. As she approached Britain, popular enthusiasm for her cause became widespread. In part, she provided an excuse for organisation and public meetings, otherwise forbidden by the 'Six Acts' but permissible because they ostensibly offered 'sympathetic addresses', which fell outside the Acts; however, the meetings were also often rambunctious and sometimes violent. London provided a major focus. The new king brought a bill of pains and penalties to be heard in the House of Lords that would dissolve the marriage and deprive Caroline of all titles and privileges. The case made its way slowly and increasingly scandalously through the House of Lords, but as it did so support for the King ebbed, and while the bill passed a third reading, it did so barely. The government abandoned it because Lord Liverpool, the Prime Minister, could not see how it would pass the Commons.

Hone and other radical satirists made much mock of the King and the government - with Hone's 'toy' - the matrimonial ladder - depicting the rise and fall of the Queen through the shabby behaviour of the King. The 'toy' had an accompanying pamphlet that spelt out in detail the sordid character of the King's behaviour.

Caroline was locked out of the Coronation in July 1821 and died the following month. While her popularity had declined after the trial, falling again in March as she accepted a £50,000 pay off, and still more sharply after her behaviour at the coronation, her funeral generated huge crowds, who seized the initiative and the cortege and forced it into a new route through the city. At one point the crowd were fired on by the Life Guards.

The whole sequence of events remains puzzling. Some historians see it as a resurgence of eighteenth-century traditional crowd behaviour, although the political and satirical value of the movement to reformers suggests that some part of the response was a function of the closure of other avenues of protest. But it is also true the catalogue of her indiscretions at the trial discredited her cause, and correspondingly increased public sympathies for the King. And the violence associated with the crowd produced in turn something of a loyalist backlash after the funeral. Perhaps the best explanation for the furore was the opportunity the case provided to ridicule and attack a king who had done little or nothing to endear himself to his people, without fear of reprisal. What is clear is that there was much to be made fun of!