Irregularities during the 2009 Iranian presidential election caused resentment among many Iranians. While post-election protests were mostly peaceful, some violence erupted, leading to clashes between security forces and protesters, while some outspoken political dissenters were detained.
However, dissenters continued to speak out against the Government, leading to further protests in December 2009. On 19 December 2009, the Grand Ayatollah Hossein Ali Montazeri, who had become a "spiritual leader" of the opposition, died. Montazeri's funeral, held on 21 December in the city of Qom, was attended by a large gathering of people and clashes ensued between security forces and mourners, leading on to further demonstrations in Qom and Isfahan. On 26 December, a paramilitary Basij force subordinate to the Iranian Revolutionary Guard stormed a mosque in Tehran where scholar and former President Mohammad Khatami was speaking. This was followed by continued clashes in Tehran in which Jaras, a news media of the critics, estimated eight to ten people had died.
Prior to Ashura, Ayatollah Kadivar said he could not "rule out the possibility" of state intervention in the planned protests.
On 27 December, demonstrations in several cities continued into the holy day of Ashura the climax of Muharram, the month of mourning. Protesters in Tehran gathered "From Imam Hussain Square to Freedom Square", "from east to west along Revolution Street", and it was on this day that "the political and religious symbology of Iran's Islamic regime was turned on its head". The protesters made another symbolic move- a "symbolic journey from a square named after its most revered hero toward a monument dedicated to freedom, along a street called Revolution."