Edgar Rice Burroughs 
Tarzan the Untamed 

Set during World War I, Edgar Rice Burroughs’ seventh Tarzan novel "Tarzan the Untamed, " begins in East Africa. John Clayton, Lord Greystoke (Tarzan) vows revenge on the Germans who have burned down his plantation and apparently killed his wife Jane. Once behind enemy lines, Tarzan wreaks havoc with the help of a lion he has befriended. Afterwards, disgusted with mankind and bereft without his true love, Tarzan wanders back into the wilds where he encounters many strange and terrible trials, and eventually learns that in fact, all may not be lost.