British monarchy

The United Kingdom operated under a constitutional monarchy.

The Doctor and the monarchy
The Doctor had numerous encounters with the Kings and Queens of Britain. So much so that Elizabeth X grew up on stories of the Doctor in the 29th century. (TV: The Beast Below)

The Doctor's relationships with the monarchs varied. The Tenth Doctor, after apparently marrying Elizabeth I (TV: The End of Time), infuriated her to the point that the next time she saw him, she ordered his execution. (TV: The Shakespeare Code) While Queen Victoria both knighted and exiled him on the same day. (TV: Tooth and Claw) However, he also had good relationships with monarchs, such as Elizabeth II. (TV: Voyage of the Damned, Planet of the Dead)

Early history
Athelstan of England was the King of England for some time in the 10th century. He received the Cup of Athelstan in 924 as a coronation gift from, King of the Welsh. (TV: Planet of the Dead)

Harold Godwinson was King of England for most of 1066. After he defeated a Viking invasion, the Normans invaded England from the south. The Monk planned to change history by using advanced technology to aid King Harold, ensuring that his army would be better able to face the Normans. This plan was defeated by the First Doctor and Harold was defeated in the Battle of Hastings by William the Conqueror, who became the new king of England. (TV: The Time Meddler)

Richard I of England, called Richard the Lionheart, was King of England during the Crusades. While he led his troops in the crusades, he worried that his younger brother John of England would usurp his throne back in England. Richard assisted the First Doctor and Ian Chesterton in rescuing Barbara Wright after her capture by Arabs. (TV: The Crusade)

King John of England ruled England in the early 13th century. While the real King John was in London taking the Crusader's Oath, the android Kamelion was being used in a plot by to sabotage Earth history by preventing King John's signing of the Magna Carta, an event pivotal to the development of parliamentary democracy on that planet. This plot was foiled by the intervention of the Fifth Doctor. (TV: The King's Demons)

Richard III of England ruled England for two years before being succeeded by Henry VII after his apparent death. (AUDIO: The Kingmaker, PROSE: Sometime Never...)

16th century
Henry VII was the King of England until his death in 1509. (PROSE: Sometime Never...)

Henry VIII was the King of England from 1509 to 1547. In his first incarnation, the Doctor claimed to have argued with Henry VIII so that he would be sentenced to the Tower of London where the TARDIS was located. (TV: The Sensorites)

After the death of Henry's successor, Edward VI, Jane Grey became queen at sixteen years as her father wished, although she never wanted to rule. On 19 July 1553, she met Rani Chandra, a traveler from 2010, on the ninth and final day of her reign. (TV: Lost in Time)

Mary I had claimed the throne and proclaimed her a traitor, intending to sentence her to death. (TV: Lost in Time)

Elizabeth I was the Queen of England in the year 1599, and an apparent spouse of the Tenth Doctor. After the Doctor broke off with her, she met a younger version of his tenth incarnation following the premiere of Love's Labour's Won, and was furious with him. (TV: The Shakespeare Code, The End of Time)

17th century
After the death of Elizabeth I some time before 1604, the Scottish King James I inherited the English throne. From then onwards, both kingdoms were ruled by a single monarch. (GAME: The Gunpowder Plot)

According to Barbara Wright, James' rule was characterised by relative religious tolerance. Though a staunch Protestant, he discouraged persecution of Catholics. Barbara claimed that he realised that "to govern well it made sense to unify people rather than drive them apart." (PROSE: The Plotters)

In spite of this, on 5 November 1605, Guy Fawkes and others attempted to blow up the Houses of Parliament and kill James I as part of a Catholic conspiracy which became known as the Gunpowder Plot. Their efforts were unsuccessful. Both the First and Eleventh Doctors were involved in these events. (PROSE: The Plotters, GAME: The Gunpowder Plot)

He was succeeded by his son Charles I, who reigned during the English Civil War. The war was fought between his supporters, the Cavaliers, and the Roundheads. The Roundheads emerged victorious and he was executed on the orders of Oliver Cromwell on 30 January 1649.

However, in 1660, his son Charles II became king after Parliament invited him to take the throne. (PROSE: The Roundheads)

Charles II, himself a Protestant, blamed the English Catholics for the Great Fire of London on 2 September 1666. (AUDIO: The Glorious Revolution) In actuality, it was started when a Terileptil weapon overloaded in a building on Pudding Lane. The Fifth Doctor played a major role in causing the fire. (TV: The Visitation)

The Fourth Doctor told Sarah Jane Smith that he met Charles II before he became king. At the time, he was on the run from the Roundheads and the Doctor helped him to hide in an old oak tree. (PROSE: The Republican's Story)

Upon his death in 1685, he was succeeded by his Catholic younger brother James II. In November 1688, his reign was brought to an end by the Glorious Revolution when he was overthrown by William of Orange. Its less immediate consequences included the Jacobite Risings which culminated in the Battle of Culloden on 16 April 1746. (AUDIO: The Glorious Revolution)

19th century
Victoria, Queen of Great Britain and Ireland, Empress of India, usually known as Queen Victoria, was a powerful and influential monarch on Earth in the 19th century. Victoria met the Doctor at least twice: once during her coronation in 1838, and in 1879 she shared an adventure with the Tenth Doctor. The latter encounter led her to banish the Doctor from her country and form the Torchwood Institute, as the British Empire's defence against the dark forces with which the Doctor seemed to consort. (TV: Tooth and Claw)

20th century
The Doctor claimed to have met Edward VII in Paris. (TV: Inferno)

Edward VIII' was King of the United Kingdom for most of 1936. He chose to abdicate before marrying the twice-divorced American Wallis Simpson. (PROSE: Players)

Elizabeth II of the United Kingdom was crowned on 2 June 1953, (TV: The Idiot's Lantern) and served well into the 21st century. (TV: Voyage of the Damned)

The alien Wire attempted to take the energy from the millions of humans watching her 1953 Coronation on their televisions. However, the Tenth Doctor foiled the Wire's plans. (TV: The Idiot's Lantern)

Students at Brendon Public School (as well as the rest of Great Britain), where the Brigadier taught, celebrated the silver anniversary of Elizabeth II's coronation in 1977. (TV: Mawdryn Undead)

In 1988, her path almost crossed that of the Seventh Doctor (who almost but not quite recognised her) at Windsor Castle as she walked her pet corgis about the grounds. (TV: Silver Nemesis)

Elizabeth II was concurrently the Queen of Australia, a situation with which not all Australians were satisfied. The Fourth and Fifth Doctor's companion Tegan Jovanka, who described herself as "downright Bolshie," favoured her country's transition from a constitutional monarchy to a republic. (AUDIO: The Children of Seth)

21st century
On Christmas Day 2006, the blood control powers of the Sycorax (operating out of a ship hovering over London) threatened to make Elizabeth II, as well as the rest of the British royal family jump off a roof and kill themselves. (TV: The Christmas Invasion)

Due to the Sycorax and "Christmas Star" incident (TV: The Runaway Bride) occuring on consecutive Christmases in London, most of the city's residents fled during Christmas 2008. The Queen staunchly decided to remain in Buckingham Palace. On Christmas Day, the alien Titanic almost crashed into Buckingham Palace; the Tenth Doctor telephoned the Palace and spoke a pre-arranged code number that resulted in the immediate evacuation of the Queen and her staff, but at the last moment he was able to pull the ship up above the palace. The Queen thanked the Doctor by name. (TV: Voyage of the Damned)

In Easter 2009, the Tenth Doctor left his TARDIS in Buckingham Palace gardens, telling Captain Erisa Magambo that the Queen did not mind. (TV: Planet of the Dead)

Various accounts have Britain ruled by a king in 1997 (TV: Battlefield, the 2000s (AUDIO: The Longest Night), and July 2012. (PROSE: The Shadows of Avalon) Whatever the date, eventually Queen Elizabeth was eventually succeeded by Charles III, along with his Queen, Camilla. Charles himself was succeeded by William V. (PROSE: Revenge of the Judoon)

In 2050, when the British government was controlled by Lomax, a Korven from the far future, Britain was ruled by a King. An Oroborus arrived on Earth around his birthday, causing time distortions which meant that some people complained about missing the King's birthday message, and others saw it twice. (TV: Oroborus)

22nd century
In 2161, during the Dalek occupation, the last monarch of Britain died. In 2199, Lord Haldoran planned to become the first monarch of Britain in thirty-eight years. (PROSE: Legacy of the Daleks)

Far future
Elizabeth X of the United Kingdom, (also known as Liz Ten) was the Queen Regnant of the United Kingdom of Great Britain and Northern Ireland during the time during which Earth was devastated by solar flares in the late 30th century. Having made herself immortal (or near-immortal), she lived for centuries (TV: The Beast Below) and lived until at least the 52nd century. (TV: The Pandorica Opens)

At some point, the British monarchy was deposed and the last monarch was executed. Footage of that event could be viewed through the Gogglebox located on the Moon. (AUDIO: The Reaping)

Alternative 17th and 18th century timeline
In an alternative timeline accidentally created by Jamie McCrimmon, the Glorious Revolution was a failure and James II retained the throne until his death. Consequently, the Jacobite Risings and the Battle of Culloden never took place. James II's grandson, Charles Edward Stuart, better known as Bonnie Prince Charlie, eventually ascended the throne as King Charles III. He was still the reigning monarch in 1788. (AUDIO: The Glorious Revolution)

Alternative 20th century timelines
In an alternate timeline in which Germany won World War II, Edward VIII was restored to the throne with Wallis as his Queen in 1940. He signed a treaty which established Great Britain as a protectorate of the German Reich. (PROSE: Timewyrm: Exodus)

The regime of a fascist Republic of Great Britain had the Royal Family executed in 1943. (TV: Inferno)

Edward IX was King of England in a more technologically advanced parallel universe. (COMIC: Who's Who?)

Alternative 21st century timelines
In a nightmare alternate timeline created by the Trickster, the starship Titanic did hit Buckingham Palace and caused a nuclear explosion. The Queen was presumed dead. (TV: Turn Left)

Alternative futures
In the Time Field timeline in 5145, Elizabeth X caught River Song attempting to steal Vincent van Gogh's painting, The Pandorica Opens. After holding River at gunpoint, she saw the painting and learned for whom it was meant before letting her go. (TV: The Pandorica Opens)

Other universes
In Arthur's World, a parallel universe, Arthur was King of England in the 8th century. (TV: Battlefield)

Torchwood website
On the series 1 version of the Torchwood website, a case file outlined the fall of Torchwood One. It suggested after a massive loss in life and technology, that it was recommended to Her Majesty Queen Elizabeth II for "the immediate closure of Torchwood One, together with the formation of a steering committee to fully examine future options."