Check this out, http://www.localhistories.org/christian.html#:~:text=The%20first%20evidence%20of%20Christianity%20in%20what%20is,be%20sure%29.%20Roman%20Britain%20was%20a%20cosmopolitan%20place. Some of the history on who wrote and why they chose specific words in the Bible is very interesting too. But Christianity didn’t happen overnight, and was not well known in England by 51 ad.