A Timeline of Capitals of England
This list was surprisingly hard to put together and I have a feeling it is still incomplete. If you know of others then please feel free to tell me. I've done my best, but given that even the definition of England is unclear for much of this history, this is always going to be a little dodgy.
The first capital that I can find record of was Colchestor in 50 CE which acted as the centre of power for the Romans. Catus Decianus was the Procurator in charge of what would later become the Kingdom of England, although the power shifted to Londinium by the end of his rule. Londonium was a Roman settlement that would eventually grow and merge with other cities to become modern day London.
As the Roman occupation left we entered a period where different Kingdoms such as Mercia and Wessex fought and competed with each other over their borders. At several points in these hundreds of years one leader or another would gain temporary recognition of control over the other Kings. This means that their various residences have been considered Capitals briefly. For instance Tamworth was promoted from being the Capital of Mercia to the Capital of England under King Offa in the 600s and Winchester (formally of the Kingdom of Wessex) became the Capital under Alfred the Great. Then in 913 Northampton was reclaimed from the Danes and it became the Capital for close to 200 years. There are plenty of other claims from around this period of varying degrees of recognition.
Eventually London became the Capital of the Kingdom of England and then later of the UK, although even this has some caveats to it because of the whole City of London compared with London itself thing and the whole City of Westminster thing. I'm not going to go there, but here's a CGP Gray video about it if you are interested.
However there was a brief interlude in London's reign because of the Civil War. As Charles I went on the run most of the places he settled temporarily became unofficial Capitals, but Oxford was the offical Royalist capital of England from 1642 onward. Cromwell claimed the City of Westminster as his Capital at the same time.
All in all this topic was messy that I regret going down this rabbit hole.