Slightly off subject but surely there is a pattern to be seen in the over throw/replacing of one religion by another. Patterns are fascinating things, they can be seen in rock art a simple stylistic expression of communication (of what we don't know - there is no key) in the structure of megalithic tombs, the choice of stone, their size, their appearance, built in a similar pattern - just as cathedrals and churches are built in a similar pattern.
Pagan has become an overcharged word but in reality it is just the difference between many different religions and the 'so called true religion'. There is a basic pattern to us humans, we settle near water, we grow food, we have a 'need' for religion (don't know why that is) at all times we conform to the nearest pattern of other social beings.
So a quoted example at Uley Bury ;

"Beneath the Roman temple are the remains of an earlier shrine, a square timber structure in a subrectangular ditched enclosure, constructed in the half century preceding the Roman conquest (AD 43). This earlier shrine itself reused earlier ditches, possible traces of a Neolithic long barrow like nearby Hetty Pegler's Tump. A temple was constructed in stone in the early second century AD, along with other buildings round about. The sanctuary continued to be maintained and modified for almost three hundred years, but showed signs of decline by the final decades of the fourth century. The temple was in much reduced form following demolition or partial collapse. Around the temple other structures too were ruinous or had been demolished by the early fifth century.However the Uley complex was not abandoned, since the site continued in use as a cult place, a rare instance of continuity from the Roman to early medieval periods. An aisled timber building with a semicircular annexe was erected on the site of the temple during the fifth century and was rebuilt in stone in the early sixth century. These structures have been interpreted as a church and baptistery, but the form and parallels of the buildings are uncertain. Carefully buried outside the annexe was the head of the cult statue of Mercury from the temple, which must have been curated for at least a century after the collapse of the building."

Rare maybe but it indicates a reverence for sacred space......