Islamism-also called Islamic Fundamentalism or Political Islam-represents one of the most important movements in the modern Islamic world. The global Muslim community is extremely diverse, and Islamist movements have taken many forms that reflect this diversity. However, most Islamists share a few common goals. These include ridding Islam of what are seen as corrupt influences and returning the faith to what they believe is an original, "pure" form; establishing Sharia as the basic law in Muslim lands; and replacing secular governments with governments that observe the tenets of Islam. This book details the historical and political context that gave rise to modern Islamist movements and groups like the Islamic State of Iraq and the Levant (ISIL). It also surveys fundamentalist movements in a variety of countries and regions, and outlines the ongoing challenges Islamic fundamentalism presents for the United States and its allies.