The taking of "Iwo Jima" from the Japanese during WWII - they needed the island as a mid-point for their attacks on Japan. It was a long, drawn out battle that had initially expected to take only a couple of days.
(I fear I may piss off some americans if i get this even slightly wrong - deep breath girl...)
Ended up being one of the biggest casualties of the Pacific war. When they took Mt Surabachi on the southern tip of the island, they climbed up and placed an American flag. All the ships and troops and everyone around cheered, thought it was fantastic, and one of the [big people?!] bosses in decided he wanted the original flag himself.
So, they took the little flag down and replaced it with a second flag, and as the six marines were hoisting it up, the infamous photo was taken.
The photo quickly circulated worldwide and became the iconic "image" to the American citizens of the capture of the island - before it was able to be confirmed that this was the
replacement flag, not the original.
Three of the flagraisers died on the island, and the remaining three returned to America as heroes - which they did not take any comfort from and felt undeserved of it. Their famous quote to everyone was:
"The real heroes of Iwo Jima were the guys who didn't come back."
The man that wrote the book is the son of Doc Bradley, one of the flagraisers, and he follows their lives from beginning to end.
It really, truly is a fantastic read - I couldn't put it down. The movie is good as well, but IMHO the book is way better.