If you look here -
http://www.ancestry.com/learn/facts/Fact.aspx?fid=10&ln=Hallmanyou will see that an English, or Swedish, OR German origin is possible, though the original German spelling had a double-L ending.
English, German and Swedish all trace back to a common ancestral language that linguistic historians have named "Old Germanic".
English word MAN is MAN in Swedish also, and MANN in German. English word HALL is HALL in Swedish and HALLE in German.