The Global Peace Index is a ground-breaking milestone in the study of peace. It is the first time that an Index has been created that ranks the nations of the world by their peacefulness and identified some of the drivers of that peace. 121 countries have been ranked by their â€˜absence of violenceâ€™, using metrics that combine both internal and external factors. Most people understand the absence of violence as an indicator of peace. This definition also allows for the measuring of peacefulness within, as well as between, nations.