Ethiopian withdrawal from Somalia (2009)
Ethiopia invaded Somalia in 2006 to oust the Islamic Courts Union and installed the transitional government. Its troops withdrew in January 2009 under a UN-brokered deal, leaving behind a weak African Union force of about 3,000 Ugandan and Burundian soldiers.
Al-Shabab quickly took Baidoa and much of southern Somalia, and the AU mission came under sustained attack in Mogadishu.
The withdrawal set the stage for a larger AMISOM surge that eventually pushed the militants out of the capital in 2011.
It shows how fast a departing foreign force can hand territory back to al-Shabab, and how a thin AU mission can become the only thing holding the capital.
