In Britain, the formation of the nation-state was not the result of a sudden upheaval or revolution. It was the result of a long-drawn-out process.
Role of ethnic groups: their cultural identities
Steady growth of the English nation steadily in case of wealth, importance and power, it was able to extend its influence over the other nations of the islands.
The Act of Union 1707—between England and Scotland.
The growth of the British identity.
Language and religious policies.