article from the NY times: The First Victims of the Crusade
Comparison of militant Islam and the crusaders of medieval times.
First victims of the crusades were Jews. The Christians descended on Jewish communities as they rode to Jerusalem. The Jews had a choice of converting or being killed.
In Mosul, Iraq, Yazidis, Muslims and Christians coexisted until ISIS arrived in 2014. The militants asked the infidels the same 900 year-old question- convert or die.
Yazidis~Zoroastrianism, Islam and Christianity.
Book by Susan Jacoby “Religious Conversion: A Secular History.”