[Excerpt - Article by Jean-Michel David, fourhares.com - Linked Above]
Was Rudolf Steiner a Freemason?
Yes.
Irrespective of the manner in which some may want to talk around this aspect of Steiner's life, he was initiated into Freemasonry, and for some time held warrants from Theodore Reuss for the Memphis-Misraïm Rite. He also set up, with those warrants, a number of Lodges under the title Misraim-Dienst [M.D.] and Mystica Aeterna [M.E.] that he eventually dissolved at the opening of the first World War. The connections are therefore exclusively with Reuss and Yarker and the rite so-named above, operating in a co-Masonic context.
Fraternally, Philip Carter / Facebook / Great is Truth and mighty above all things (I Esdras 4:41)