Protesting has been strongly associated with areas that are majority Sunni and often older or poorer districts of the city...though some recent suburbs have been just as deeply involved.
The government, dominated by the Alawite sect, made some concessions to the majority Sunni and some minority populations.
The majority Sunnis argued that the elders of the community would elect a leader, or caliph, but the minority Shiites insisted that only descendants of Muhammad and his family could succeed him.
The Government does not conduct census on religion, but estimates put the percentage of the majority Sunnis at 85-90% while Shiites, who comprise the largest Muslim minority, at 10-15% of the population.
However, all schools of Islam, including the majority Sunnis, regard Zayd as a righteous martyr (shahid) against what is regarded as the corrupt leadership of the Umayyads.
There are also non-Arab Muslims like the Kurds, who are majority Sunni, and Iranians, who are mainly Shiite, plus members of other religions.
Turkoman - 2% : This group has a minor role in the current situation (majority Sunni with large Shi'a minority), although Turkey is concerned about their overall treatment in Iraq.
It was not without inner turmoil; a lasting schism formed between majority Sunnis and minority Shiites.
And likewise the army is majority Sunni.
Now, some Muslim communities are so large that the majority Sunnis and minority Shiites maintain their own mosques, schools and social clubs.