First and Foremost

Wikipedia's page on this subject.

Military

• Most wars (even those fought before the 18th century) were not fought over religion. Roughly 7-10% of wars in recorded history can effectively be traced to religion as the primary cause. While it's true that many wars use religion as a type of rallying cry or point of unification, the main causes of the war diverged quite severely and usually centered on the "common" causes of war which usually include political and economic differences and resource distribution and allocation.
  
  
• A "casualty" does not mean "death." Famously, everyone likes to quote that the 442nd Japanese-American regiment had more casualties than the total people in the Lost Battalion they were sent in to save. Whenever I'm in a documentary or lecture covering this, I always hear people gasp and say something akin to "more people died than the number they were trying to save?" Err.. no...  While it's true that the cost in terms of casualties was rather high, these folks are missing the point.
  
  A casualty is any type of anything sustained in combat that renders the combatant unable to function on the battlefield during that (and maybe subsequent) action (and, yes, death renders a person unable to function on a battlefield) or any injury sustained that requires some type of attentive care in order to prevent future death or disablement and return that soldier to a combat-ready state. Coming up as missing also renders someone a casualty. Getting shot, stabbed, or punched in the face can, and probably will, render a soldier a casualty. But badly stubbing a toe could cause a casualty as well. Also, a soldier could get injured but continue to function as a combatant until the battle is over at which time he or she would receive medical care. A soldier in this position could also be listed as a casualty. As such, a battle could have a 100% casualty rate, but everyone could survive it. In the same ken, a battle could have a 100% casualty rate and 100% death rate. 
  
  One veteran I knew was listed as a casualty and received a Purple Heart because a Japanese scout plane flew low and dislodged a coconut that subsequently hit him on the head. The bonk to the dome precipitated a gash that took several stitches to close. Yup, he was a "casualty."