When getting a travel insurance quote, country of residence is required.
The primary residence is the country where the traveler lives. If the residence is in the U.S. or Canada, then the state or province will be entered as well. If the traveler has multiple places of residence, then the location that serves as the mailing address will be the residence.
The country of residence can determine which products are eligable for that quote. There are also some policy benefits that are excluded for residents of various states. They can include cancel for any reason, rental car damage, or identity theft.
Always refer to the certificate of insurance for details.