Inhabited since at least the 15th century B.C., Gaza has been dominated by many different peoples and empires throughout its history; it was incorporated into the Ottoman Empire in the early 16th century. Gaza fell to British forces during World War I, becoming a part of the British Mandate of Palestine. Following the 1948 Arab-Israeli War, Egypt administered the newly formed Gaza Strip; it was captured by Israel in the Six-Day War in 1967. Under a series of agreements known as the Oslo accords signed between 1994 and 1999, Israel transferred to the newly-created Palestinian Authority (PA) security and civilian responsibility for many Palestinian-populated areas of the Gaza Strip as well as the West Bank. Negotiations to determine the permanent status of the West Bank and Gaza Strip stalled in 2001, after which the area witnessed a violent intifada or uprising.   Israel by late 2005 unilaterally withdrew all of its settlers and soldiers and dismantled its military facilities in the Gaza Strip, but it continues to control the Gaza Strip’s land and maritime borders and airspace. In early 2006, the Islamic Resistance Movement (HAMAS) won a majority in the Palestinian Legislative Council election. Attempts to form a unity government between Fatah and HAMAS failed and violent clashes between their respective supporters ensued, culminating in HAMAS's violent seizure of all military and governmental institutions in the Gaza Strip in June 2007. Since HAMAS’s takeover, Israel and Egypt have enforced tight restrictions on movement and access of goods and individuals into and out of the territory. Fatah and HAMAS have since reached a series of agreements aimed at restoring political unity between the Gaza Strip and the West Bank but have struggled to effect them; a reconciliation agreement signed in October 2017 remains unimplemented.   In July 2014, HAMAS and other Gaza-based militant groups engaged in a 51-day conflict with Israel — the third conflict since HAMAS’s takeover in 2007 — culminating in late August with an open-ended truce that continues to tenuously hold despite the absence of a negotiated cease-fire and periodic attacks. The UN in 2015 published a study assessing that the Gaza Strip could become uninhabitable by 2020 unless steps are taken to address Gaza’s economic and humanitarian situation. In September 2018, the UN reported that conditions were worse than when its experts made that prediction.