Order of Merit
The Order of Merit was founded by king Edward VII as a special honour to reward personalities for great achievements in art, science or literature. It is the sole gift of the Sovereign and the membership of the order is limited to 24 members. In addition, an unrestricted number of foreign recipients can be honoured, although there are only a few of them who have been admitted.
Former British members of the Order of Merit have included: Florence Nightingale and Lord Lister (medicine); Alma Tadema, Holman Hunt, Augustus John and Graham Sutherland, Henry Moore (artists); Sir Edward Elgar, Ralph Vaughan Williams and Benjamin Britten (composers); Thomas Hardy, James Barrie, T. S. Eliot, E. M. Forster, Graham Greene and Ted Hughes (literature) as well as former Prime Ministers Winston Churchill and Clement Attlee.
Sources:
http://www.royal.gov.uk/MonarchUK/Honours/OrderofMerit/OrderofMerit.aspx