Catuvellaunorum

The Catuvellauni were a Celtic tribe or kingdom of ancient Britain. Their territory encompassed the modern counties of Hertfordshire, Bedfordshire, and parts of Cambridgeshire and Essex. The name is believed to derive from the Brythonic words "catu" meaning battle, and "vel" meaning might or power, suggesting they were a formidable people.

The Catuvellauni are primarily known through Roman historical accounts, particularly those of Julius Caesar and later Tacitus. They were one of the most powerful tribes in southern Britain, often in conflict with neighboring tribes, most notably the Trinovantes. In the decades before the Roman invasion of 43 AD, the Catuvellauni, under their formidable king Cunobelinus, rose to prominence and exerted considerable influence over a large part of southeastern Britain. Cunobelinus is often depicted as a powerful ruler, sometimes even referred to as "King of the Britons" by Roman writers.

Following the Roman conquest, the Catuvellauni territory became an important part of the Roman province of Britannia. Their capital, believed to be Verulamium (modern St Albans), was established as a civitas and grew into a significant Roman town. While the tribe itself was integrated into the Roman administrative system, their warrior reputation and independent spirit were noted by Roman observers. The Catuvellauni played a role in subsequent British history as part of the Roman province and in the post-Roman period.