Wonder why he didn't? And had the best script possible.
He could have got one of Wayne's better performances.
Why wasn't Ray Teal, Lee Van Cleef and Neville Brand Cast?
JOHN FORD's ALAMO starring THE DUKE!
Could have been the Great Classic.
Apparently, Duke considered John Ford and then decided to direct it himself. It was a very personal choice. Duke's friend's have said that his biggest mistake was in accepting the script as written by James Edward Grant. Initially Duke wanted to focus on historical accuracy, but Grant wanted to make many "deviations" for dramatic development. Afterwards, Duke said that the movie was "emotionally accurate."
To give credit where credit is due, I got the above from Scott Eyman's terrific biography of John Wayne. If you like Duke, or hate him, I recommend you hunt it down and read it.
Agreed, Grant's script,which often becomes clichéd and overblown and downright corny at times, is the weakest part of the film. Ford or Hawks would never have gone with the script as written.
Wayne also never wanted to play a leading role, his original idea was to play the small but important role of Sam Houston. But the investors in the film insisted that Wayne play a leading role,and he chose Crockett.