First enter any country to choose it from the drop-down list. Then, name the administrative divisions shown for that country. I tried to use first-level administrative divisions but in some cases they are 2nd level. The divisions sometimes are official and sometimes just census-based areas – some small countries may not have administrative divisions and you may be naming island/atolls/etc. Divisions are ordered by highest population first. Some alternate names are accepted but for many you must know the full division name. Overseas territories are usually not included for countries unless they are parts of that country’s administrative divisions.
For a handful of countries (more to come) I have multiple options, so for France you will see ‘France 1st’ and ‘France 2nd’ – this corresponds to 1st and 2nd level administrative divisions options.
2nd-level divisions may take a few moments to load (especially US counties).