This command sets the controller of a specified province to the specified country tag (if no country tag is specified, the country that you're playing as will become the controller).
control [province id] [country tag]
|Province ID||The ID of the province you wish to change the controller of.|
|Country Tag||Optional. The country tag of the country you wish to make the controller of the specified province. If a country tag is not specified, the country you are currently playing as will become the controller of the specified province.|
Vilna's province ID is 272, this command would make the country you are currently playing as the controller of Vilna.
control 272 ARM
As Armenia's country tag (ARM) has been specified, this would make Armenia the controller of province ID 272, which is Vilna. Find a list of all province ID on our province ID list.