The Western Frontier Force was raised from British Empire troops during the Senussi Campaign from November 1915 to February 1917, under the command of the Egyptian Expeditionary Force (EEF). Orders for the formation of the force were issued on 20 November 1915, under Major-General Alexander Wallace, C.B. The force concentrated at Mersa Matruh on the coast and began operations against the Senussi in late 1915.

The Senussi campaign took place in North Africa from November 1915 to February 1917, during the First World War. The campaign was fought by the Kingdom of Italy and the British Empire against the Senussi, a religious order of Arabic nomads in Libya and Egypt. The Senussi were courted by the Ottoman Empire and the German Empire. Recognising French and Italian threats, the Ottoman Sultan Abdulhamid II had twice sent his aide-de-camp Azmzade Sadik El Mueyyed to meet Sheikh Muhammed El Mehdi El Senussi to cultivate positive relations and counter the west European scramble for Africa. In the summer of 1915, the Ottomans persuaded the Grand Senussi Ahmed Sharif as-Senussi to declare jihad, attack British-occupied Egypt from the west and to encourage insurrection in Egypt to divert British forces.