Norman De Mattos Bentwich OBE MC, was born in 1883 to a British Zionist family. He attended St Paul's School in London, and Cambridge's Trinity College.
Bentwich visited British Mandate Palestine in 1908 after the beginning of his assignment as delegate to the Zionist Congress in 1907. He continued this delegation through to the 1912 Congress. He served as Senior Judicial Officer during the British military administration of Palestine, and then in 1920 when the administration became civil, Bentwich became Legal Secretary. The title was changed to Attorney General, and he held the post till 1931.
Bentwich had a large part to play in the development of the law of Palestine, but became unpopular with Palestinian Arabs as his perceived Zionist bias came to the fore. Due to this, he was seen as a liability by some and they pushed for his dismissal. During the Shaw Commission into the August riots of 1929 he was barred from representing the government. In August 1931, Bentwich was dismissed by the Under Secretary of State for the Colonies due to the racial and political conditions that were specific to Palestine.
In November 1929, Bentwich was shot in the leg by a 17 year old Arab employee of the Palestine Police. The assailant was sentenced to 15 years hard labor, even with Bentwich advocating for him.
From 1932 until 1951 he served at Hebrew University of Jerusalem as Chair of International Relations. He was a follower of Achad Ha'am and wrote a book about his mentor, Ahad Ha'am and His Philosophy. In 1929 he joined Brit Shalom, a society to develop better relations between Jews and Arabs in Palestine.
He later became President of the Jewish Historical Society.
Bentwich authored Life and Times of Josephus, as well as Mandate Memories. He was a barrister and legal academic and lived till April 1971.