Reuven Firestone 
Jihad [PDF ebook] 
The Origin of Holy War in Islam

While there exists no evidence to date that the indigenous inhabitants of Arabia knew of holy war prior to Islam, holy war ideas and behaviors appear already among Muslims during the first generation. This book focuses on why and how such a seemingly radical development took place. Basing his hypothesis on evidence from the Qur’an and early Islamic literary sources, Firestone locates the origin of Islamic holy war and traces its evolution as a response to the changes affecting the new community of Muslims in its transition from ancient Arabian culture to the religious civilization of Islam.