Board Thread:New on Arrowverse Wiki/@comment-1854917-20160325081032/@comment-27178728-20160601182243

You are right, but for the Constantine argument, Wendy Mericle confirmed that the thirteen episodes of the first and only season of Constantine occur in the same Earth that Arrow, Earth One: http://ca.ign.com/articles/2015/08/12/arrow-constantine-will-help-bring-sara-lance-back