As FU said Mehnis, war was what caused us to need men to protect us from other men. This caused men to start viewing us as chattle, the same as their cows, and eventually this lead to formal rules on behaviour being written into law codes and religion. Something which has taken us 200 years to break away from.

"We submit to the majority because we have to. But we are not compelled to call our attitude of subjection a posture of respect." Ambrose Bierce