Complex sentence: The attack by the Senussi on Egypt had not helped the Ottoman Empire to defeat the British east of the Suez Canal and the majority of the Egyptian population did not join the jihad and rise against the British.
Split into simpler sentences: The attack by the Senussi on Egypt did not allow the Ottoman Empire to defeat the British east of the Suez Canal. The majority of the Egyptian population did not join the jihad and rise against the British.