Hajj Umar, al-
al- Hajj Umar (äl-häj ōōmär´) or Hajj Omar (ō´mär), 1797–1864, Muslim religious and military leader in W Africa. A chieftain of the large Tukulor tribe of Senegal, he desired to convert the pagan tribespeople of the W Sudan. Declaring a holy war in 1852, he used modern weapons against the Africans. In several engagements (1857–59) against the French in Senegal, he was repulsed. Thereafter he turned eastward, conquering the kingdoms of Segu and Massina and sacking Timbuktu. He was killed in 1864 while attempting to put down a revolt by the Fulanis, a Muslim group living in Massina. Bitter quarrels over his domain by his sons weakened it, and in 1890 it was annexed by the French.