This one’s a pretty easy themeless, perhaps equivalent to a Tuesday/Wednesday in the NYT puzzleverse.
5D: While not really obscure, this is the least common answer in the grid, although according to Wikipedia he is considered “one of the best military commanders and strategists of all time.”
49D: I wasn’t sure how commonly known this bird was, so the tail end of the clue tries to give a humorous hint.
Jeff's Puzzles 