At what time did the earliest Christian communities emerge in Britain?

Christianity's arrival in Britain wasn't a sudden event, but rather a gradual introduction. While legends link it to even earlier times, concrete evidence places the emergence of organized Christian communities in the 3rd and 4th centuries. The Roman Empire, which controlled Britain during this period, initially persecuted Christians. However, Emperor Constantine's conversion in the early 4th century, and the subsequent Edict of Milan in 313 AD, granted religious tolerance, allowing Christianity to spread more freely. Archaeological finds like mosaics with Christian symbols and early church sites support this timeline. So, while individual Christians might have been present earlier, the establishment of identifiable Christian communities really took root in the 3rd and 4th centuries, making that the most accurate answer. The other options are off because the 1st and 2nd centuries have very little evidence of organized Christian presence, and the 4th and 5th centuries are a bit too late, as Christianity was already taking hold by then.