Sorry, it was a messy post - was at work on a busy day

Basically I was saying that the Grail legend had Messianic overtones and connections, because you could look at many aspects of them, and their connection to characters and places in Christian lore, to see glimpses of an attempt to reconcile early Christianity with Welsh and Celtic mythology. It's not easy to summarize, because there are a lot of variants of the legends with different forms written by various writers over time (the most famous are Chretien de Troyes and Sir Mallory, who wrote 'L'Morte d'Arthur' but I'll try my best so that you can see where I was coming from.

According to ancient traditions regarding inheritance, the reigning king became one with the land by marrying the queen, which may indicate a matrilineal chain of succession, where the matriarch holds lands and titles, and her consort inherits rulership of these through her. So the queen was synonymous with the land, and the king was her chosen consort. This is the connection that later came to be known as the identification of the Fisher King with the health and wellbeing of the land. There are some interpretations that this is why Queen Gwenevere was so important to Camelot; once the union between her and Arthur were severed, he no longer had the right to reign, and the land suffered.

The title 'Messios' was used to refer to the Fisher King in the 'Perlesvaus', where it could be seen as an attempt to render 'Messiah' into the language and culture of the ancient Welsh and/or Celtic legends. King Bran the Blessed (who is also called 'Bron' in some myths) is mentioned as having received a wound in his thigh, and he spent most of his time fishing. According other legends mentioning Bron, he was called The Rich Fisher, because he attended to Jesus and the disciples at the last supper. In 'The Romance of Perceval/Didot Perceval), the chapter 'The Castle of the Fisher King', states that King Bron was Percevals' grandfather, and that he was the current guardian of the Grail. This idea had appeared before, in the 'Mabinogion' - Bran was said to possess the magical cauldron of healing. The holy grail or sangraal seems to have been identified with their legends of the magical cauldron. King Pellas in these legends also has a connection to Biblical lore - he was said to be the direct descendant of Joshua.

The Arthurian legends later developed to suggest that he would return as a messiah to restore justice and health to the land, which is parallel to the role Jesus' return would have. You could even look at the variants of this aspect of the legend, in which Arthur is said to run with the Wild Hunt as an Arthurian version of the Book of Revelation.