The BBC's Frank Gardner asks whether Isis - the small but fanatical jihadist army - can rule the large tracts of Syria and Iraq it has conquered.
Iraq's insurgency has been spearheaded by Isis, but it is only one of several Sunni groups involved, says Aymenn Jawad Al-Tamimi.
- Iraqi mortuaries 'struggling to cope'04:10
- 'We terrify Isis': BBC meets Shia militias06:34
- Isis bulldozes into 'Islamic state'01:46
- Iraq refugees: Life during Ramadan02:29
- BBC's Bowen: What is a 'caliphate'? 02:33
- Footage 'shows Iraq flash operation' 01:05
- The Iraqi Christians who refuse to flee01:55
- Sunni fighters: BBC exclusive interview02:45
- Iraqi forces 'fighting back'02:17
- Iraq: UN warns of impact on minorities02:27
- Sniper footage shows battle against Isis03:47
- Defiant Shia parade in Baghdad 01:00
- Raw video of BBC under ISIS attack04:56
Features and Analysis
The background to the latest insurgency
What Isis will do now that it's swept through Syria and Iraq
Sunni rebels in Iraq face Isis allegiance dilemma
Why Isis caliphate is bad news for the Muslim and non-Muslim world
The problems in getting jihadist posts taken off social media
Will beleaguered PM Nouri Maliki be able to stay in office?
ISIS advance does not spell end of Iraq yet, says John Simpson
How has Mosul changed since extremists swept in?
How far can US military advisers help ease the crisis?
Why common cause in Iraq will not hasten warmer US-Iran ties
Crisis has dealt Iraq a mortal blow, says Fawaz Gerges
ISIS militants eye lucrative Iraqi resources
Could Iraq crisis boost Kurdish dreams of independence?