Use this pattern when your process or application requires the user to select a country.
Country selection list
User experience
Using flags to help with country selection can be visually appealing and intuitive for users. it is also important to list them alphabetically. It can also help usability to create a short list of the most commonly selected countries that appear in the list first, to help with usability and to prevent users having to scroll through an long list to get to the United Kingdom or United States for example.