As I understand it, British knighthoods are never - or maybe rarely - awarded posthumously. Is that right? There are many people on this list, 100 Greatest Britons - Wikipedia, who I think deserve to receive knighthoods for their contributions to the United Kingdom, who were not so honoured during their lives. Right off the bat, I’d say Brunel, Darwin, Shakespeare, Cook and Tolkien. What do you think?
And while the topic is up, I would like to know if Robert Hardy has been knighted.
No, a knight is somebody who is ranked at that level within his or her chivalric order. Robert Hardy is only a Commander of the Most Excellent Order of the British Empire (a CBE, the third highest rank), not a Knight Commander (KBE) or Knight Grand Cross (GBE).
Note however that there is more than one way to skin this cat. Sir Paul McCartney, for instance, is only an MBE - the lowest rank of the Order, and so not a “Sir” by that route - but he is also a Knight Bachelor.
I hereby dub this thread a Knight Commander of the Order of Moved to IMHO.