I'm also finding scattered references of Medieval Arians who baptized in Jesus name and provided shelter to other antitrinitarian Monarchian (Oneness) groups. They proliferated the Gothic Bible, a translation that was considered to challenge various Trinitarian notions of the Latin Bibles of their time. Not to mention early Celtic missionaries who appear to have practiced baptism in the name of Jesus prior to the arrival of the Catholics. It appears that they took the
Acts 2:38 message to Languedoc, Flanders, Frisia and Saxony.
I'm going to have to do a lot of cross referencing to verify because these little snippets of information are peppered throughout various historical works. But it leaves the door wide open to reveal quite a witness to the truth down through history.