During the Victorian era, one quarter of the globe was under British rule. At the time, the British had the largest Empire in history, and England was the most powerful nation on Earth. Britannia ruled the waves, although 'Britannia' eventually gave up the name to an airline and a building society.
At the head of the greatest army of the time were the officer classes, public schoolboys and Oxford or Cambridge graduates, calling each other nicknames such as Bunter, Charmers, Strangely Brown and Dave Dee, Dozy, Beaky, Mick and Tich. The calmness under fire of these officers is best ridiculed by the 'African War' scene in Monty Python's film The Meaning Of Life.
It could be assumed that the British Empire was founded on five main principles:
That anyone who went to Eton, Oxford or Cambridge should get a position of power and a knighthood.
That anyone who didn't go to Eton, Oxford or Cambridge should be forced to work for a pittance to help maintain the Empire, and should be forced to be cheerful and cockney.
That the best possible type of leader for an African province was a British one who went to Eton, Oxford or Cambridge...
That people should know their places in society and call their betters 'sir'.
That capital punishment was the best possibly preventative for re-offending.
The Empire came to greatness by killing lots of people less sharply armed than themselves and stealing their countries, although their methods later changed: killing lots of people with machine guns came to prominence as the army's tactic of choice.
The Empire didn't so much fall, as get disassembled into its component parts. India and parts of the Americas fell off first, followed by great lumps of Africa.
Many people might think that everybody else's mighty armies crushed the British, but not a bit of it. The empire actually fell to pieces because of various people like Mahatma Gandhi, heroic revolutionary protester, sensitive to the needs of his people.
Nowadays, the British Empire consists of the UK and a few islands scattered around the globe like geographical confetti, and the only military moves the British make outside of the United Nations and NATO is the sending of football hooligans to the Continent and young nightclubbers on package tours to Ibiza.