Appointed to the post by his friend Henry II, as a person who the king thought was very much on his side, Becket soon went native, and his friendship with the king was tested as he stood up for the church in its disagreements with the king. In 1164, he was even forced to flee briefly to exile in France, only returning in 1170.
The situation didn't improve when Becket excommunicated the new King, Henry the Young King in York, for having his coronation in York as opposed the traditional, church-chosen venue of Canterbury. Subsequently, in 1170, four knights, believing the king wanted Becket out of the way, assassinated him in Canterbury Cathedral.
In 1973, a statue to Becket falling to the ground, designed by Edward Bainbridge Copal, was erected among the bushes on the south side of St Paul's cathedral. Your author presumes it may be symbolic of the three blows it apparently took to make Becket fall down upon his assassination, following which he is said to have offered himself a living sacrifice, and said in a low voice, 'For the name of Jesus and the protection of the Church, I am ready to embrace death'.
For more on Becket, visit http://en.wikipedia.org/wiki/Thomas_Becket