Having read the Esquire article, I'm a bit of a know-it-all about TH. 
It said that while his parents were divorcing they paid for him to go to Eton to have the best education they could give him. And he used the money he got from acting jobs while he was at Cambridge to pay for RADA. So he doesn't come from an uber posh background.
It also said that his sisters told him he was very like the Jonathan Pine character.