Joined: Jan 2010
Posts: 9,805
Likes: 1,772
From: Northern California
Bikes: Cheltenham-Pedersen racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.
If the freewheel won't spin freely onto an English-threaded hub, then it's likely French-threaded.
I always use a little WD40 on the threads when such doing test fits, in case there is thickened grease present.