10 Worst Changes Peter Jackson Made To The Lord Of The Rings
4. Éomer's Role Was Massively Reduced
The character of Éomer in the films was actually a combination of two book characters. You'd think this would give him a larger role, but conversely it diminished his part. Peter Jackson made the decision to cut a number of characters from the movie, but several had roles that needed to be fulfilled.
Erkenbrand was the Marshal of the Westfold, and was responsible for leading the defences against Saruman. His forces were scattered after the Battle of the Fords of Isen, but Gandalf gathered them to the lift the siege of Helm's Deep. In the films Jackson essentially folds this sub plot into Éomer's. But it resulted in Éomer being absent for much of the Two Towers.
In the books he was imprisoned by Théoden, not banished. Upon Gandalf's arrival he is freed and joins the Rohan forces at Helm's Deep. During the battle he forms a fighting friendship with Aragorn and the two are responsible for defending the Deeping Wall, not the elves, but we'll get to that later...