Hello, thank you so much for your kind words for " Birds Of A Feather " they are much appreciated. Also happy to know what type of birds they are :) My son said they where eating out of his hand, they are such beautiful birds.
No, Thomas a Beckett wasn't killed at this church, which was built in Yorkshire (in the north) almost a 100 years after his murder, but in his own cathedral at Canterbury, on the steps of the altar, in 1170. As you say he was martyred by the king (Henry II) for opposing Henry's plan to expand and consolidate secular power by eliminating the religious courts of justice and bringing all judicial matters under control of the crown. Henry had appointed Thomas as Archbishop of Canterbury (the top religious post in England), assuming, because of their long and close friendship, that he could depend on Thomas to support him and his efforts completely, but Thomas ended up siding with the Pope and the Church. He was canonized soon after his martyrdom, and a number of churches have taken him as patron saint and been named for him.
I discovered these details at http://www.eyewitnesstohistory.com/becket.htm.