Once upon a time, when Celtic tribes populated Britain, the Yew tree was revered as a symbol of longevity and rebirth and would be worshipped as such. This continued under Roman occupation, too, but such practises were stopped when the Empire converted to Christianity.
Many Yew trees now can be found in churchyards, much like the one that houses the Crowhurst Yew because Christian's often built their places of worship over that of the Pagan's as a way to supplant the religion.
Appearance-wise you could imagine that the Crowhurst Yew would be right at home in Fangorn forest, the ancient woodland of J.R.R Tolkien's