July 6, 2013 - Ahmad Assi Jarba is elected the new leader of the Syrian National Coalition.
August 1, 2013 - U.N. spokesman Martin Nesirky tells reporters that a team of ten experts has been assembled to travel to Syria to investigate three reports of chemical weapons use.
August 2, 2013 - The U.N. calls for an investigation into an incident in July in Khan al-Assal in northern Syria. Videos on the internet purport to show Syrian rebels executing as many as 30 people, most of them government soldiers.
August 18, 2013 - A team of U.N. weapons inspectors arrives in Syria to begin an investigation into whether chemical weapons have been used during the civil war.
August 22, 2013 - The United Nations and the United States call for an immediate investigation of Syrian activists' claims that the Bashar al-Assad government used chemical weapons in an attack on civilians on August 21. Anti-regime activist groups in Syria say more than 1,300 people were killed in the attack outside Damascus, many of them women and children. Video footage and witness reports appeared to bolster claims that chemical weapons were used.
August 23, 2013 - U.N. Secretary-General Ban Ki-moon says the use of chemical weapons in Syria is a crime against humanity and must be punished.
August 24, 2013 - Medical charity Doctors Without Borders announces that three hospitals near Damascus treated more that 3,000 patients suffering "neurotoxic symptoms" on August 21. Reportedly, 355 of the patients died.
August 26, 2013 - U.N. inspectors reach the site of a reported chemical attack in Moadamiyet al-Sham, near Damascus. En route to the site, the team's convoy is hit by sniper fire. No one is injured.
August 26, 2013 - U.S. Secretary of State John Kerry describes the suspected chemical weapons attack "inexcusable" and says, "President Obama believes there must be accountability for those who would use the world's most heinous weapons against the world's most vulnerable people."
August 27, 2013 - U.S. Secretary of Defense Chuck Hagel says that if the President Obama orders a strike on Syria, U.S. defense forces are "ready to go."
August 29, 2013 - The U.K.'s Parliament votes against any military action in Syria.
August 30, 2013 - U.S Secretary of State John Kerry says that U.S. intelligence information has found that 1,429 people were killed in last week's chemical weapons attack in Syria, including at least 426 children.
August 31, 2013 - U.S. President Barack Obama gives a speech asking Congress to authorize military action against Syria.
September 9, 2013 - Syria agrees to a Russian proposal to give up control of its chemical weapons.
September 10, 2013 - In a speech before the U.S. public, President Obama says he will not, "put American boots on the ground in Syria" but does not rule out other military options.
September 14, 2013 - The U.S. and Russia agree to a plan to eliminate chemical weapons in Syria.
September 16, 2013 - U.N. Secretary-General Ban Ki-moon releases the report from chemical weapons inspectors who investigated the August 21 event. The inspectors say there is "clear and convincing evidence" that sarin was used.
September 20, 2013 - Syria releases an initial report on its chemical weapons program.
September 27, 2013 - The U.N. Security Council passes a resolution requiring Syria to eliminate its arsenal of chemical weapons. President al-Assad says he will abide by the resolution.
September 30, 2013 - At the U.N. General Assembly in New York, Syrian Foreign Minister Walid al-Moualem says that Syria is not engaged in a civil war, but a war on terror.
October 6, 2013 - Syria begins dismantling chemical weapons program, including the destruction of missile warheads and aerial bombs.
October 31, 2013 - The Organisation for the Prohibition of Chemical Weapons announces that Syria has destroyed all its declared chemical weapons mixing, filling and production facilities.
November 25, 2013 - The U.N. announces that starting January 22 in Geneva, Switzerland, the Syrian government and an unknown number of opposition groups will meet at a "Geneva II" conference meant to broker an end to the Syrian civil war.
December 2, 2013 - U.N. human right chief Navi Pillay says that a U.N. fact-finding team has found "massive evidence" that the highest levels of the Syrian government are responsible for war crimes.