This Saturday, in a lavish ceremony, King Charles III will have a crown officially placed on his head, a ceremony known as the Coronation.
These days, it is only a formality, because Charles became King automatically when his mother Queen Elizabeth II died, a process known as accession. Some other countries don’t even have coronation ceremonies at all.
But back when kings had armies, a coronation was confirmation that the institutions of state supported that person, and was confirmation that the person ruled the country. Real power did not start until after they had been formally crowned.
The military parade showed that the army supported the ruler.
The anointing and blessing showed that the ruler had the support of the religious institutions, and through them, the support of God.
The details have changed, but this ceremony is a descendent of coronations in Ancient Egypt, the Bible, the Roman Empire, and the Middle Ages.