Almohad doctrine (Arabic: الدَّعوَة المُوَحِّدِيَّة) or Almohadism was the ideology underpinning the Almohad movement, founded by Ibn Tumart, which created the Almohad Empire during the 12th to 13th centuries. Fundamental to Almohadism was Ibn Tumart's radical interpretation of tawḥid—"unity" or "oneness"—from which the Almohads get their name: al-muwaḥḥidūn (المُوَحِّدون).