The British told them they would be free after the war was over.
If this is for a class, this might not be the answer you’re looking for.
America has always been against immigration. Even as it was being built on the backs of immigrants from Europe, the colonists who were already here despised them. Xenophobia has been a part of American culture since it was founded. This long history with anti-immigration and nationalism coupled with white supremacy makes many Americans wary toward immigrants today.
Answer:
he believed the confedarate force around the city was much larger than his.