The percentage of the male population that is circumcised in each one of 237 countries was determined from reviews of various types of surveys. For countries with no survey data, estimates were used based on religious and cultural groups that circumcise in the countries and their proportions of the populations.
The Global Peace Index ranks countries for their levels of peacefulness. The state of peacefulness is determined using three categories: the level of Societal Safety and Security, the extent of Ongoing Domestic and International Conflict, and the degree of Militarization.
Average circumcision rates were determined for the 30 most peaceful countries and 30 least peaceful countries in the Global Peace Index.
The most peaceful countries had an average circumcision rate of 10%.
The least peaceful countries had an average circumcision rate of 68%.
References:
Estimation of country-specific and global prevalence of male circumcision, 2016 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4772313/
Global Peace Index, 2016 data used https://en.wikipedia.org/wiki/Global_Peace_Index#Global_Peace_Index_rankings_(2008%E2%80%932019)