Zulu! is one of the most accurate ever. All of he battle scenes are meticulously accurate to real life accounts. The only liberty the writers took was the portrayal of the missionary. He didn’t have a pretty young daughter, and he wasn’t a peacenik as depicted in the movie. In fact he helped bring ammo and water to the soldiers.
Khartoum is fairly accurate, except for the portrayal of the Mahdi who was not western educated and had never been outside of the Sudan. Neither did Gordon go meet with him. Other than that though it’s pretty much factual.
Loved Zulu. Great soundtrack too.