Thomas Spence, a schoolteacher from Newcastle arrived in London in December 1792. Over the next twenty-two years Spence developed a reputation as an important radical figure in Britain. He wrote books, pamphlets and produced a journal, Pigs Meat, where he argued for the radical transformation of society. The publication of this material resulted in him enduring several periods of imprisonment.

Spence did not believe in a centralized radical body and instead encouraged the formation of small groups that could meet in local public houses. At these meetings Thomas Spence argued that "if all the land in Britain was shared out equally, there would be enough to give every man, woman and child seven acres each". At night the men walked the streets and chalked on the walls slogans such as "Spence's Plan and Full Bellies" and "The Land is the People's Farm". In 1800 and 1801 the authorities believed that Spence and his followers were responsible for bread riots in London. However, they did not have enough evidence to arrest them for this offence.

Thomas Spence died in September 1814. He was buried by "forty disciples" who pledged that they would keep his ideas alive. They did this by forming the Society of Spencean Philanthropists. The men met in small groups all over London. These meetings mainly took place in public houses and they discussed the best way of achieving an equal society. Places used included the Mulberry Tree in Moorfields, the Carlisle in Shoreditch, the Cock in Soho, the Pineapple in Lambeth, the White Lion in Camden, the Horse and Groom in Marylebone and the Nag's Head in Carnaby Market.

The government became very concerned about this group that they employed a spy, John Castle, to join the Spenceans and report on their activities. In October 1816 Castle reported to John Stafford, supervisor of Home Office spies, that the Spenceans were planning to overthrow the British government.

On 2nd December 1816, the Spencean group organized a mass meeting at Spa Fields, Islington. The speakers at the meeting included Henry 'Orator' Hunt and James Watson. The magistrates decided to disperse the meeting and while Stafford and eighty police officers were doing this, one of the men, Joseph Rhodes, was stabbed. The four leaders of the Spenceans, James Watson, Arthur Thistlewood, Thomas Preston and John Hopper were arrested and charged with high treason.
James Watson was the first to be tried. However, the main prosecution witness was the government spy, John Castle. The defense council was able to show that Castle had a criminal record and that his testimony was unreliable. The jury concluded that Castle was an agent provocateur (a person employed to incite suspected people to some open action that will make them liable to punishment) and refused to convict Watson. As the case against Watson had failed, it was decided to release the other three men who were due to be tried for the same offence.

The Spenceans continued to meet after the trial but the members now disagreed about the future strategy of the group. Arthur Thistlewood was convinced a successful violent revolution was possible. James Watson now doubted the wisdom of this strategy and although he still attended meetings, he gradually lost control of the group to the more militant ideas of Thistlewood.

The government remained concerned about the Spenceans and in January, 1817 John Stafford asked a police officer, George Ruthven, to join the group. Ruthven discovered that the Spenceans were planning an armed rising. Arthur Thistlewood claimed at one meeting that he could raise 15,000 armed men in just half an hour. As a result of this information, John Williamson, John Shegoe, James Hanley, George Edwards and Thomas Dwyer were also recruited by Stafford to spy on the Spenceans.

The Peterloo Massacre in Manchester increased the amount of anger the Spenceans felt towards the government. At one meeting a spy reported that Arthur Thistlewood said: "High Treason was committed against the people at Manchester. I resolved that the lives of the instigators of massacre should atone for the souls of murdered innocents."

On 22nd February 1820, George Edwards pointed out to Arthur Thistlewood an item in the New Times that said several members of the British government were going to have dinner at Lord Harrowby's house at 39 Grosvenor Square the following night. Thistlewood argued that this was the opportunity they had been waiting for. It was decided that a group of Spenceans would gain entry to the house and kill all the government ministers. The heads of Lord Castlereagh and Lord Sidmouth would be placed on poles and taken around the slums of London. Thistlewood was convinced that this would incite an armed uprising that would overthrow the government. This would be followed by the creation of a new government committed to creating a society based on the ideas of Thomas Spence.

Over the next few hours Thistlewood attempted to recruit as many people as possible to take part in the plot. Many people refused and according to the police spy, George Edwards, only twenty-seven people agreed to participate. This included William Davidson, James Ings, Richard Tidd, John Brunt, John Harrison, James Wilson, Richard Bradburn, John Strange, Charles Copper, Robert Adams and John Monument.

William Davidson had worked for Lord Harrowby in the past and knew some of the staff at Grosvenor Square. He was instructed to find out more details about the cabinet meeting. However, when he spoke to one of the servants he was told that the Earl of Harrowby was not in London. When Davidson reported this news back to Arthur Thistlewood, he insisted that the servant was lying and that the assassinations should proceed as planned.

One member of the gang, John Harrison, knew of a small, two-story building in Cato Street that was available for rent. The ground-floor was a stable and above that was a hayloft. As it was only a short distance from Grosvenor Square, it was decided to rent the building as a base for the operation. Edwards told Stafford of the plan and Richard Birnie, a magistrate at Bow Street, was put in charge of the operation. Lord Sidmouth instructed Birnie to use men from the Second Battalion Coldstream Guards as well as police officers from Bow Street to arrest the Cato Street Conspirators.
Birnie decided to send George Ruthven, a police officer and former spy who knew most of the Spenceans, to the Horse and Groom, a public house that overlooked the stable in Cato Street. On 23rd February, Ruthven took up his position at two o'clock in the afternoon. Soon afterwards Thistlewood's gang began arriving at the stable. By seven thirty Richard Birnie and twelve police officers joined Ruthven at Cato Street.

The Coldstream Guards had not arrived and Birnie decided he had enough men to capture the Cato Street gang. Birnie gave orders for Ruthven to carry out the task while he waited outside. Inside the stable the police found James Ings on guard. He was quickly overcome and George Ruthven led his men up the ladder into the hayloft where the gang was having their meeting. As he entered the loft Ruthven shouted, "We are peace officers. Lay down your arms." Arthur Thistlewood and William Davidson raised their swords while some of the other men attempted to load their pistols. One of the police officers, Richard Smithers, moved forward to make the arrests but Thistlewood stabbed him with his sword. Smithers gasped, "Oh God, I am..." and lost consciousness. Smithers died soon afterwards.

George Cruikshank, Cato Street Conspiracy (1820)

Some of the gang surrendered but others like William Davidson were only taken after a struggle. Four of the conspirators, Thistlewood, John Brunt, Robert Adams and John Harrison escaped out of a back window. However, George Edwards had given the police a detailed list of all those involved and the men were soon arrested.
Eleven men were eventually charged with being involved in the Cato Street Conspiracy. After the experience of the previous trial of the Spenceans, Lord Sidmouth was unwilling to use the evidence of his spies in court. George Edwards, the person with a great deal of information about the conspiracy, was never called. Instead the police offered to drop charges against certain members of the gang if they were willing to give evidence against the rest of the conspirators. Two of these men, Robert Adams and John Monument, agreed and they provided the evidence needed to convict the rest of the gang.

On 28th April 1820, Arthur Thistlewood, William Davidson, James Ings, Richard Tidd, and John Brunt were tried at the Old Bailey and having been found guilty, the Lord Chief Justice sentenced them as follows “That you, each of you, be taken hence to the goal from whence you came, and from thence that you be drawn on a hurdle to a place of execution, and be there hanged by the neck until dead; and that afterwards your heads shall be severed from your bodies, and your bodies divided into four quarters, to be disposed of as his Majesty shall think fit. And may God of His infinite goodness have mercy upon your souls”. John Harrison, James Wilson, Richard Bradburn, John Strange and Charles Copper were also found guilty but their original sentence of execution was subsequently commuted to transportation for life. Thistlewood, Davidson, Ings, Tidd and Brunt were executed at Newgate Prison on the 1st May, 1820.
At 8 o'clock the drop fell and they were suspended. It took about five minutes for all visible signs of life to be extinguished, but they were left on the ropes for half an hour to ensure total death. The bodies were then drawn back up onto the platform and placed on their coffins with the neck of each over a small block set at the end of each coffin in turn. The rope was removed and each head severed by a masked man using a surgical knife. Their executioners showed each of the heads to the crowd proclaiming "This is the head of a traitor". It is thought that a medical man or a butcher actually performed the decapitation.
With this another cruel punishment passed into history.

Hanging, drawing and quartering.
The above form of execution was called hanging, drawing and quartering. Hanging, drawing & quartering remained the lawful punishment for High Treason until abolished in 1870. It was not used often as it was considered so barbaric. Governments of the day were concerned about public opinion even in those days. Ordinary hanging (until dead) replaced it, although the Monarch could still order beheading and quartering of the body, but the cutting down of the prisoner whilst still alive and the disemboweling and burning of his organs ceased. It was not until the Forfeiture Act of 1870 that all reference to drawing and quartering was removed from the Statute Book, however.
It is interesting to note that men convicted of Petty Treason and High Treason offences such as coining were not subjected to drawing & quartering, being just drawn on the hurdle to the place of execution and hanged in the normal way, and yet women convicted of these offences were burnt at the stake until 1789. It is unclear why this was. Peers of the Realm who were convicted of High Treason were beheaded.