As heir to the throne, Prince Charles will become King when the Queen sadly passes.
Most expect him to rule as the nation's Sovereign, and many expect he will be known as King Charles III.
However Charles can choose to reign under a different name to his birth name, just like many previous kings and queens did.
Charles was born Charles Philip Arthur George, and there have been whisperings for years that Charles wishes to reign as King George VII.
He could adopt the regnal name of George in tribute to his grandfather, the current Queen's father, King George VI.
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Reigning as the next King George could also symbolise continuity for the House of Windsor, as Charles' great-grandfather also reigned as King George V.
Speaking to Studio 10 in 2005, former royal butler Grant Harrold said: "Normally royal children have two or three names. The reason is, if possibly that child was to become a king or queen, they have to have a kind of pool to choose from.
"For example, Prince Charles, if and when he becomes king, would be - people assume he would be Charles III. But he could technically be George VII because George is in his name."
If Charles were to choose his first name, he would reign as King Charles III, however, royal commentators predict he will decide against this due to negative connotations surrounding the two former King Charles.
Charles I, who became king in 1625, dismissed parliament three times and resolved to rule alone four years later. He reigned without a Parliament for more than a decade, a period which was dubbed 'eleven years' tyranny'.
Following two civil wars, Charles was tried and convicted of being a 'tyrant, traitor, murderer and public enemy to the good people of the nation' and was beheaded for treason on January 30, 1649.
His son, Charles II, lived in exile until he was crowned King of England, Ireland and Scotland in 1661.
He was popular and dubbed "the Merry Monarch", changing laws brought in by Oliver Cromwell and allowing people more freedom to enjoy themselves. However, he also lived a controversial lifestyle, fathering at least 14 illegitimate offspring.
It is unlikely Prince Charles will want to take on the moniker, however, we won't know for sure until he ascends the throne.
