Using StackSets to deploy resources to multiple regions

If you have a CloudFormation template that you have authored in order to create resources in a single region, what happens when you want to deploy those same resources into another region, or even another account? You could manually create the stacks, or you could string together a few CLI scripts to do the job for you; but, there's a better way.

StackSets allow you to deploy a template across multiple regions and accounts, in a way that is fully managed by CloudFormation.

Getting ready

Before you can use StackSets, you must establish an account to be the administrator account, and then you must create roles in the administrator account and in the target accounts...