Yemen’s embattled President Abdel-Rabbo Mansour Hadi resigned Thursday after failing to reach a power-sharing agreement with Shi’ite rebels who have held Sana’a, the capital, since September.
Hadi’s departure leaves Yemen’s fate in the balance. The poorest nation in the Arab world is fractured by tribal fighting, a separatist movement in the south, a robust Al-Qaeda presence, and the rising influence of the Shi’ite rebel group known as the Houthis.
But Yemen is no stranger to turmoil. In the images above, TIME looks at key moments in the country’s past that provide a historical context for the unfolding unrest.