With the Coronation of King Charles III and Queen Camilia on the 6th May, let us look briefly to see where this tradition came from.

In 597 Pope Gregory I sent St Augustine to Britain to convert the Pagans. He was the first Archbishop of Canterbury and introduced the coronation ceremony to many kingdoms in Britannia. 

Edgar the Peaceful was crowned in Bath and his Archbishop organised a ceremony similar to one of charlamagne, the frakish king and holy roman emperor. This forms bases of all coronations since, although theyhave been slightly modified with each new monarch. The main sections are:
1)Recognition and oath
2)Anointing
3)Investing of Regalia
4)Crowning
5)Enthronement & Homage

In 1066, William the Conqueror was crowned in Westminister Abbey,  which was built by Edward the Confessor who was also crowned there.
Westminister Abbey has hosted 25 monarch coronations, 15 Queen Consort coronations, and 15 joint coronations.

Norman kings usually held seperate coronations to their queen consorts but in 1154 Queen Eleanor of Aquitiaine insited on being coronated with Henry II. Since then, if the King is married and on good terms with his wife then they would be cornated together.

When Henry III died, Edward I (his son) was away on a crusade got crowned in Sicily when got the news. From then on coronations became symbolic and the reign of a new monarch began when their predecessor died. Coronations were also held several months after the death of the previous monarch to allow sufficient time for mourning and planning.