Leo: ...were born with a distinct birthmark symbolising the rise from Salem's ashes.
This is not a reference to witches being burnt at the stake in Salem, Massachusetts, since witches were not burnt at the stake in Massachusetts. Only Melinda Warren, an entirely fictional character, seems to have been burnt at the stake. Thus this is actually a reference to rising from the ashes of the biblical city of Jeruselam, often referred to as Salem. 2nd Chronicles 36: 15-23 speaks of its destruction by the Babylonians, with 2nd Chronicles 36: 19 stating "They set fire to God's temples and broke down the wall of Jerusalem; they burned all the palaces and destroyed everything of value there."