Program on Roman occupation of UK and Boudicca, indicated on map an area around Sussex, not occupied. Why so?

Question

Occupied by the Romans.
Map observedon "Warrior Women" subject, Boudicca, the History Channel.

Answer 1

Not occupied by who?

The Romans were there and it was one of the most settled areas of the country. Boudicca wasn't there because she knew after destroying Colchester and London (as they are now known) that she had to defeat the governor quickly before her army fell apart. So, she went after him, going west and not south. He was returning from Anglesey after destroying the centre of the Druidic worship there. No one fought there because it wasn't important strategically.