The Iraqi Civil War was a period of great civil unrest and sectarian violence that lasted from early to mid 2012. After American forces left the country, conflict between the nation's Sunni and Shia population intensified. Iraq's armed forces were unable to maintain order as violent conflict spread throughout the nation. Following a devastating terrorist attack against the country's government, the unstable Iraqi government collapsed completely. The conflict that followed resulted in the deaths of over 300,000 Iraqis and would prompt military intervention by Saudi Arabia and Iran.