An identification is the most important document to present to the authorities, either in the United States or abroad, to obtain a marriage license. Your and your foreign spouse's picture ID (driving licence or passport) is universally required around the U.S. to apply for a licence, while individual states have additional requirements. Connecticut, for example, also asks for your Social Security number, your mothers' maiden name, your parents' birthplaces, date and location of your wedding, as well as the name and contact info of your wedding officiant. Check the "U.S. Marriage Laws" website for details on each state's and county's requirements.