Should history be told by the perspective of the winners or losers? I want to write a claim with several paragraphs based on the conflict between...

Interesting question, because you identify something that historians know is almost inevitable--history will have bias.  Look at the history of American exploration.  If told from the side of the victors, the Europeans, one would think that white people came to save North America and North Americans in the name of progress and God.  If told from the side of the vanquished, the native Americans, one would say that the Europeans came and declared an unjust war and waged genocide on both their people and culture.  If read one way, the history of North America reads like an adventurous story of exploration; if read another way, it reads like an indictment of germ warfare and genocide.  The ideal history would be a combination of the two tales--a retelling of events from both sides that would let the reader make the decision for himself/herself.  History is more than the retelling of events; history is also the ability to read critically and make one's own decisions.