Vietnam have been a victim of wars and oppressions almost their whole existence. After the dynasties era, Vietnam was colonized by the French and oppressed by chinese domination, followed by the Indochina war. After the Vietnam war, vietnamese villages were troubled by the Cambodian Khmer Rouge so they fought against the Khmer as well.
There are numerous museums all over Hanoi such as War museum, Revolutionary museum, Army museum, Military museum, Prison museum & Ho Chi Minh's very own museum, and many more (!). I'm not proud to say that I've visited all of them... they are pretty much the same, but very informative!