Queen Elizabeth II, who died on Thursday at the age of 96, has been an integral part of British life, and her passing has left a void in the lives of her subjects.

A lot of things have already changed since the Queen's death, and several others associated with her reign will need to be changed as the new King takes over the reins.

The monarch's portrait, emblems, and iconography adorn coins, banknotes, stamps, flags, and passports. The Queen's face will now be replaced with the face of King Charles III.

According to a report in The Guardian, there are 4.5 billion sterling banknotes in circulation with the Queen's face emblazoned on them. All these notes will gradually be removed from circulation.

The Queen's image also appears on some $20 banknotes in Canada and coins issued in New Zealand, as well as other parts of the Commonwealth. These countries may also replace the existing legal tender with new ones.

The most straightforward change would be in the national anthem. "God save our gracious Queen" will be replaced by "God save our gracious King."

The British passport will also have some changes in the pronouns used for the monarch.

The passport states: "Her Britannic Majesty's Secretary of State requests and requires in the name of Her Majesty all those whom it may concern to allow the bearer to pass freely without let or hindrance and to afford the bearer such assistance and protection as may be necessary."

Therefore, the new passports that will now be issued will bear the male pronouns. Existing passports may only be updated once they have expired.

The Commonwealth nations that recognise the monarch as their head of state may also need to change their constitutions. However, countries like Australia, Canada, and New Zealand already have systems in place that will ensure the new monarch automatically becomes head of state.

All British MPs pledge allegiance to the Crown after being elected to the parliament.

They take the oath: "I...swear by almighty God that I will be faithful and bear true allegiance to Her Majesty Queen Elizabeth, her heirs and successors, according to law. So help me God."

All of that will now change, and the MPs will now be required to pledge allegiance to the new King, Charles.

Britain's Queen Elizabeth with her son Charles. Reuters / Toby Melville