hold up my friend chantry didnt let merideth rule they just stayed neutral and how would it look if the chantry did step in? Just to some but like it or not merideth kept the power vaccum in check. I dislike their practices on magi and uniformity but sometimes they are right
The Chantry did get involved with a trade dispute with Dumar's predecessor. He was taxing Orlesians more than other countries, so the Chantry ordered Meredith's predecessor, Knight-Commander...er, forgot his name to get involved and help Orlais out. He said no, it was not a templar's duty to get involved with politics.
This little exchange however had the Viscount kill him and attempt to drive out the templars from Kirkwall entirely. Meredith took control of the Templars as she was Knight-Captain, led the assault and arrested him. He was tried and sentenced by Elthina and Dumar was selected as the new Viscount. It was kind of an open secret however that Meredith was in charge unofficially, even before Hawke arrived.
Hawke: Knight-Commander's orders? That's a templar title.
Guard: Well Dumar may be Viscount, but Meredith is the power in Kirkwall. I'd hate to see what would happen if he did something she didn't want.
This little exchange is before Act 1 even starts.