Peerages of England, Great Britain, and the United Kingdom follow English law; the difference between them is that Peerages of England were created before the Act of Union 1707, Peerages of Great Britain between 1707 and the Union with Ireland in 1800, and Peerages of the United Kingdom since 1800.

When did the British aristocracy begin?

The current form of the British peerage has been a process of evolution. While the ranks of baron and earl predate the British peerage itself, the ranks of duke and marquess were introduced to England in the 14th century.

When were barons created?

The title of baron was most generally introduced into southern Italy (including Sicily) by the Normans during the 11th century. Whereas originally a barony might consist of two or more manors, by 1700 we see what were formerly single manors erected into baronies, counties or even marquisates.