The expression is an idiom which means to cause increased interest and excitement. So to expand on Jura's point the villagers were very excited at the arrival of the actress and this and this might have caused a commotion/trouble

It means that the people were very excited to see the actress and probably a lot of them tried to see her in person.

I agree with what is said above. However, I just want to add that 'cause a stir' or 'cause a commotion' does not only mean 'excitement' that is felt by a number of people, but it also means 'cause people to become agitated, angry or shocked; cause trouble in a group of people.'

a commotion.