What did the north believe about the war when it first started?

If you're talking about the civil war than, when the war first started the fight wasn't for slavery at all it was more for Abe Lincoln just wanting to have the confederates back into the union and to be united. The only reason Lincoln made a rule that slaves could be free was to hurt the south. This hurt the south because slaves made up some of the southern army and slaves were the ones who had to also work on fields and do other labor so a slave could escape to the north and he wouldn't be brought back to the south.