Emily Dickinson's poem "Witchcraft was hung, in History" reminds many about the history of witchcraft in America and England. The topic of study for many within the high school English class walls are not unfamiliar with Arthur Miller's "The Crucible."
The poem speaks to the fact that witchcraft holds a very distinct place in history. Here, Dickinson is recognizing this fact by stating that it (witchcraft) is hung (a reference to the hanging of accused witches during the witch trials) in History (capitalized for significance).
In the next line, Dickinson befriends History by referring to "History and I", "we", and "us."
The last set of lines states that both Witchcraft and Dickinson are still able to find witchcraft around them even given the fact it was already "hung" up prior.
What Dickinson means to convey in the poem is that even though parts of history are hung up (meaning in the past and presumably over/gone) she can still see aspects of it around her every day. Basically, Dickinson is feeling sentimental about the past, but joyful that she is able to recognize it is still around.