Founded in the 1950s, the Daawa Party is the oldest of the Shia Islamist movements. After a series of attempts to assassinate Saddam Hussein and some of his ministers, it was harshly suppressed and the group eventually split into several factions.
The party's spokesman, Ibrahim al-Jaafari, is an influential member of the Iraqi Governing Council.
Another senior Daawa member, Ezzedine Salim, was killed in a bombing in May 2004, when he held the rotating presidency of the council.
A senior Daawa figure, Sheikh Mohammed Nasseri, has returned to southern Iraq from exile in Iran as part of an attempt by the party to re-establish itself after years of clandestine existence.
Sheikh Nasseri has said: "The most dangerous thing is to prolong the occupation period of the coalition forces. We hope the period will be shorter than six months."