This 2009 History Channel series details the Roman invasion and subjugation of Britain starting in the first century BC.

From imdb:

“Sifting through writings, relics, and ruins, historians piece together the time before, during and after the Roman invasion of Britian.”

“They decimated cities while building new ones in their destructive path.  They killed thousands while bringing civilization to the remaining population.  Rome's British invasion and nearly 400-hundred-year rule was a paradoxical campaign of annihilation and growth.  This three-part exploration of the Roman Empire's occupation of Britain examines why they attacked, where they conquered, how they industrialized and exploited the land and what made them vulnerable to the revolt that signaled the ultimate fall of Rome.”