BBC News Hamas is the largest of several Palestinian militant Islamist groups. Its name is an Arabic acronym for the Islamic Resistance Movement, originating as it did in 1987 after the beginning of the first intifada, or Palestinian uprising, against Israel's occupation of the West Bank and Gaza Strip. It originally had a dual purpose of carrying out an armed struggle against Israel - led by its military wing, the Izzedine al-Qassam Brigades - and delivering social welfare programmes. But since 2005, it has also engaged in the Palestinian political process, becoming the first Islamist group in the Arab world to win election through the ballot box (before reinforcing its power in Gaza by ousting its Fatah rivals).