History is very important it answers a lot of are life daily questions for example how the United States became and independent country or how African Americans became slaves and how Abraham Lincoln is such an important president and how the civil war still impacts of very much to this day.
That is because Engels presented things much worse than they actually were so as to prove a point and spread his ideology. Of course that a little bias was necessary for that since it had to motivate people that they had it worse than they really had it.