It seems like I always knew about Attenborough from The Great Escape, which we watched in elementary school. Later I saw him play an American sailor in The Sand Pebbles, which became one of my all-time favorite movies, but it was years before I realized it was the same guy. And it was still later that I put together that he was the "Dickie" they were referring to in the Monty Python's Flying Circus "Light Entertainment Awards." And of course he directed a number of good movies, the "star-studded" war picture A Bridge to Far being one I enjoyed many times over the years.
A great talent, presence and body of work.