With the death of Queen Elizabeth II, her son Charles has become King Charles III.
He comes to the throne bearing the name of one of Britain's most ill-fated monarchs.
King Charles I died under an executioner's axe on a Whitehall balcony in 1649 after losing the English Civil War.
His son Charles II fled overseas, only to return and take the throne.
He had more than 10 illegitimate children, but left no legitimate heir, instead handing the throne — and the responsibility of looking after his many mistresses — to his brother James.
Here's a quick guide to the reigns of the first two kings named Charles.
A king in chains
The first King Charles was the son of King James VI of Scotland (James I of England), and a grandson of Mary, Queen of Scots.
He ruled from 1625 until his execution following the English Civil War.
Charles I's early reign was marked by quarrels with parliament over his authoritarian rule.
He came to the throne as England was engaged in war with Spain. He also started a war with France on the advice of the Duke of Buckingham, his key advisor.
Failed campaigns in those wars led to an attempt by the government to impeach Buckingham on treason. To prevent this, Charles I dissolved parliament.
At the same time, Charles I attempted to implement taxes and loans to fund the military campaigns without the government's approval.
He also courted controversy in marrying Henrietta Maria, a Roman Catholic and sister of the French King Louis XIII, at a time when anti-Catholicism was at its height. Catholics were banned from holding office, and Anglicanism was legally enforced.
By 1629, four years into his rule, the government passed three resolutions condemning the king's behaviour.
In response, for the next 11 years Charles I ruled without calling a parliament, collecting money for the monarchy through new fines and taxes.
By the 1640s, a civil war was brewing. The country was divided between parliamentarians and monarchists — the Roundheads and Cavaliers — amid controversy over how England, Scotland and Ireland should be governed.
It was Charles I's hope to unite the kingdoms of England, Scotland and Ireland into a single kingdom.
Many English parliamentarians feared such a kingdom might destroy old English traditions. They were also suspicious of his views on the divine power of the crown; that kings were chosen and empowered by God.
War broke out in 1642, with royalist armies fighting against parliamentarian forces across the country.
In 1645 a string of battlefield successes by the parliamentarians, aided by a Scottish rebellion, forced Charles I to surrender.
He surrendered to the Scots, rather than the English parliamentarians, in a bid to exploit divisions between the alliance.
An ensuing second civil war was short-lived, as the now royalist-backed Scottish invasion was swiftly defeated by Oliver Cromwell and Lord Fairfax's New Model Army.
Forced once again to surrender, Charles I was put on trial, found guilty of high treason, and removed from the throne.
On January 30, 1649, he was beheaded in front of a large crowd in London.
A king returns
The second King Charles reigned from 1660 to 1685.
Born in 1630, the first surviving son of Charles I and Henrietta Maria, his teenage years were marred by the civil war, moving around battlefields and safe houses and into exile.
During the second civil war, Charles II lived in the Hague, where it was believed his mother's French connections would help him attract support.
It was here the first of Charles II's rumoured several illegitimate children was conceived after a brief affair with noblewoman Lucy Walters.
The execution of Charles I in January 1649 granted Charles II the throne — in theory.
In practice Cromwell's forces were determined not to see him on the throne.
When the Scottish Covenantor parliament proclaimed Charles as king, it started the third and final civil war of the period.
The English parliamentarians invaded Scotland with Cromwell's New Model Army.
A number of defeats on Scottish soil led Charles II in a last-ditch effort to invade England, but he was decisively beaten at the Battle of Worcester in September 1651.
In the aftermath, the defeated Scottish government was dissolved, and the English parliament absorbed the kingdom of Scotland into the Commonwealth.
Despite renouncing his Scottish loyalties, Charles II was forced into exile in France and later Spain, while Cromwell ruled the British Commonwealth under military rule until his death in 1658.
Cromwell's son Richard succeeded him, but his incompetence led to unrest within the New Model Army.
Tensions resulted in parliament dissolving itself, and the newly elected House of Commons was evenly divided on royalist rule.
The charismatic Charles II promised to rule in cooperation with parliament and successfully negotiated the return of the monarchy.
He arrived in London in May 1660 after being proclaimed King in Dublin.
One of his first acts was to have Oliver Cromwell's body dug up and beheaded.
In 1661, Charles married the Portuguese princess Catherine of Braganza. She, like his mother, was a Roman Catholic.
Catherine never bore a child, suffering a number of miscarriages throughout the marriage which lasted until Charles II's death.
In 1665, the Great Plague of London hit.
The outbreak lasted 18 months and killed some 100,000 people — a quarter of the city's population at the time.
Charles II fled to Salisbury to avoid the disease.
Mere months after the plague, the great Fire of London engulfed the city.
The fire consumed around 13,200 homes and 87 churches, including St Paul's Cathedral.
Overseas wars and his increasing support for Catholicism saw Charles II grow unpopular with parliament.
Seen as a weak king who was more interested in hosting lavish parties and carrying on a series of affairs than in governing, in the later years of his rule he dissolved parliament several times.
In 1685, Charles II suffered a sudden apoplectic fit and died, aged 54. The manner of his death and his unpopularity seeded suspicions of poisoning.
He converted to his wife's religion on his deathbed.
Modern medical opinions suggest the symptoms of his final illness were similar to those of uraemia — a syndrome related to kidney dysfunction.
He was succeeded by his brother James II, who he asked to look after his mistresses.
James was to be even more controversial, and was deposed in the so-called Glorious Revolution of 1689.
