A huge new online survey of Iranians reveals only 40% identify as Muslim.
The history of the Iran-United States relationship is complex and often brutal. Understanding it helps put today's turmoil into sharper focus.
'Zulm,' an Arabic word meaning extreme injustice, could explain why Iran appears to be so united in anger at the US killing of Gen. Qassam Soleimani.
Hostility to Iran's revolution from both the West and in the region is as virulent now as it was in February 1979.
Reformers have tried to modernise Iran for decades but have failed mainly due to the country's powerful theocracy. And then there are those who want to overthrow the regime altogether.
The Iranian Revolution was a hard-fought battle for those in favour of the Islamist model of governance, inspiring similar movements that have had varying degrees of success across the region.
Ever since the shocking spectacle of the Iranian Revolution and hostage crisis, American conservatives have reserved a special disdain for the Islamic Republic.
A mummy unearthed during construction in Iran may be the body of a former shah. For the Islamic regime, the discovery is an unwelcome reminder of Iran's secular past. For protesters, it holds promise.
Iran's young "daughters of the revolution" are protesting hijab laws and demanding equal rights. They're the ultimate symbol of female resistance on this International Women's Day.
Protests against mandatory hijabs have a clear goal, and if successful, would be a victory for Iranian civil society.
11 activists have died in prison since Iran's mass protests were crushed in January. Now, some detainees' families are keeping a daily vigil outside jails. It's a sign that unrest in Iran is not over.
Shared economic and security interests have kept Saudi Arabia and the US close over the decades despite dramatic differences in the way the two countries are governed.