How did Christianity become th dominant religion in europe?

The following is information obtained from the A&E documentary "The Unknown Jesus", the Wikipedia entry "Buddhism and Christianity", and The Catholic Encyclopedia.

There are reports of Jesus visiting other countries, going as far north as ancient England to meet the Druids. This seems to coincide with the large amount of Jesus' young adult life that is missing from The Bible. Jesus was brilliant in the respect that instead of preaching to the leaders of countries who would have surely persecuted him, he preached to the poor and gave them confidence in their ability to obtain heaven. While the rich have power, the poor are many and Word travels fast. It seems to me that this partially explains Britain's willingness to accept Christianity.

British legend has it that Joseph of Aramathea, a successful tin merchant, brought Jesus on at least one occasion to Britain. According to the Catholic Encyclopedia, Joseph of Aramathea was the great uncle of Jesus. However, according to John 19:38-42, he was a secret disciple of Jesus and he took it upon himself to give Jesus a proper resting place. Joseph of Aramathea and Nicodemus were the ones to care for newly-deceased Jesus and to lay it in the tomb. According to the Gospel of Nicodemus, it was Joseph's very own tomb which he and Nicodemus put Jesus. The Catholic Encyclopedia goes on to say that Joseph of Aramathea was one of the first Christian missionaries to visit Britain and some time after the cruxifixion of Jesus, he established the first church in the British Isles, which developed into Glastonbury Abbey.