Question

Which state was the last to abolish slavery in the north?

Answer 1

Some northern states had not abolished it yet at the time of the Civil War

Explanation:

Slavery was not officially abolished in most Northern states though it almost disappeared unlike in the South where it was a rooted institution. For instance there were still slaves in New Jersey(very few) and Delaware when the Civil War broke out.

More details: http://www.civildiscourse-historyblog.com/blog/2017/1/3/when-did-slavery-really-end-in-the-north