Quick'n'dirty reversion of https://github.com/nuket/google-sheets-geocoding-macro/ for extracting country names from a list of free-text strings

extract-country.gs

function extractCountries() {
  var sheet = SpreadsheetApp.getActiveSheet();
  var cells = sheet.getActiveRange();
  
  if (cells.getNumColumns() != 2) {
    Logger.log("Must select the Location, Country.");
    return;
  }
  
  var addressColumn = 1;
  var addressRow;
  
  var countryColumn = addressColumn + 1;
  
  var geocoder = Maps.newGeocoder();
  var location;
  
  for (addressRow = 1; addressRow <= cells.getNumRows(); ++addressRow) {
    address = cells.getCell(addressRow, addressColumn).getValue();
    if (address && address != "") {
      location = geocoder.geocode(address);
      if (location.status == 'OK') {
        var components = location["results"][0]["address_components"];
        var country = components[components.length-1]["long_name"];
        cells.getCell(addressRow, countryColumn).setValue(country);
      }
    }
  }
};

function onOpen() {
  var sheet = SpreadsheetApp.getActiveSpreadsheet();
  var entries = [{
    name: "Extract countries",
    functionName: "extractCountries"
  }];
  sheet.addMenu("Macros", entries);
};