Complex sentence: She is also known for the 1943 pamphlet for the U.S. Army called "The Races of Mankind", which she co-wrote with Ruth Benedict, meant to teach military personnel about the cultural differences between the peoples of the world.
Split into simpler sentences: She is also known for the 1943 pamphlet for the U.S. Army called "The Races of Mankind", which she co-wrote with Ruth Benedict. It was intended to educate military personnel about the cultural differences among the peoples of the world.