Why didn't Grima....

[TheLostPilgrim]

I forget if this is a film invention or not....But Grima held sway with Theoden, did he not? He had Theoden sort of under his control?

If so, why didn't he coerce Theoden into SIDING with Saruman--Having Rohan's armies join with Saruman's?

[Inziladun]

I forget if this is a film invention or not....But Grima held sway with Theoden, did he not? He had Theoden sort of under his control?

If so, why didn't he coerce Theoden into SIDING with Saruman--Having Rohan's armies join with Saruman's?

In the books, Wormtongue's influence over Théoden was not a secret. Gandalf made the remark that everyone except Théoden knew the man as "Wormtongue".

Saruman probably thought (correctly, I believe) that inaction by Théoden would be enough to allow him to accomplish his goals, and that an overt alliance with him would have met with enough resistance from both the military and the commoners to have made it difficult to enact. Wormtongue would likely have been turned out, if not killed. Walking the fine line that he did served Wormtongue's purpose, without needless risk.

[Mithalwen]

I need to check unfinished tales which provides a lot more detail ab8ut the Rohan situation, the plan was to get rid of Theodred and Eomer out of the way and then take over. Grima would forcibly marry Eowyn and use her blood right to give legitemacy to his authority. Saruman was stymied by the timely arrival of Gandalf aided by the courage of the likes of Elfhelm to act independently 8f orders and go to the aid of Theodred. Delaying Saruman's forces just long enough for Gandalf to arrive and Merry and Pippin to rouse the ents made all the difference in what would have been a very unequal struggle.

[popo]

I need to check unfinished tales which provides a lot more detail ab8ut the Rohan situation, the plan was to get rid of Theodred and Eomer out of the way and then take over. Grima would forcibly marry Eowyn and use her blood right to give legitemacy to his authority. Saruman was stymied by the timely arrival of Gandalf aided by the courage of the likes of Elfhelm to act independently 8f orders and go to the aid of Theodred. Delaying Saruman's forces just long enough for Gandalf to arrive and Merry and Pippin to rouse the ents made all the difference in what would have been a very unequal struggle.

This seems to be in line with how it was playing out. However, I think it would have still involved open war. Grima would have been the Rohan Quisling, after Saruman had conquered, and needed a puppet ruler. Eowyn was his reward.
Open war was upon them already, afterall. The Isengard forces had taken the foords and scattered Erkenbrand's troops. Saruman had then completely emptied Isengard of troops for a death stroke against Rohan. This was before Grima had arrived to tell him of Gandalf's arrival. Unless it was that Saruman's sighting of the three hunters, or the fact his Orc ring hunting party never returned that caused him to launch the assault on Rohan early.