In which year did the Roman army depart from Britain?

Alright, let's talk about when the Romans packed their bags and left Britain. Roman rule in Britain lasted for nearly 400 years, starting with the invasion in AD 43 under Emperor Claudius. They built roads, towns, and forts, leaving a lasting impact on the landscape and culture. However, by the early 5th century, the Roman Empire was facing increasing pressure from invading tribes elsewhere in Europe. They needed their legions to defend the heart of the Empire. So, in AD 410, Emperor Honorius sent a letter to the cities of Britain, telling them they would have to look to their own defenses. This is generally considered the end of Roman rule in Britain. While some Roman influence lingered, the organized Roman army and administration were gone. AD 43 is when they arrived, AD 630 is way too late, that's well into the Anglo-Saxon period, and AD 100 is too early in the Roman occupation. So AD 410 marks the definitive departure.