When did old English develop?

Old English developed over a period of time, but it's generally accepted that it emerged as a distinct language around the 5th century AD. This period coincides with the arrival of Germanic tribes, primarily the Angles, Saxons, and Jutes, to Britain.

Here's a more detailed breakdown:

* 449 AD: The traditional date for the arrival of the Anglo-Saxons in Britain, marking the beginning of the period where Old English started to take shape.

* 5th - 11th centuries AD: This is considered the era of Old English, with its gradual evolution from a mix of Anglo-Saxon dialects.

* 1066 AD: The Norman Conquest of England introduces Norman French, which significantly influences the English language, paving the way for the development of Middle English.

It's important to remember that language development is a continuous process, and Old English itself underwent various stages of change within its lifespan.