Which foreign fighters are in the highest numbers in ISIS and why?

ISIS began by a man named al-Zarqawi in 1999. He and his followers created ISIS in order to make people believe that the leader of Islam was among their group of followers. To do this, ISIS had to fight the rest of the world. Many people from all over the world are recruited over the Internet to join ISIS by promising them a great life. The people know that they must face other soldiers and fight for them, but they also will have a great afterlife.

Since ISIS began in the Middle East and is currently fought there, it is not difficult to believe that most of their recruits come from the countries in the Middle East like Pakistan, Turkey, and Bosnia. However, the countries that are close to the Middle East like African countries located in close proximity to the Middle East also supply soldiers to ISIS.