Before 1948, there wasn't a Snap-on wrench line really. Thats where Blue Point came in. Blue Point was marketed along side Snap-on as the same quality.
After 1948, Blue Point was still available as a separate line, but Snap-on offered what look to me to be the same wrench with a different name. I have several wrenches from before 1948 and after. They are the same and I believe most have the same part #. Later on, Blue Point came out with a "Supreme" line, but I only have them in tappet and open end configurations so I don't know if "Supreme" was available in all Blue Point wrenches.
What has been said about the current Blue Point line being imported from Taiwan is correct, but be careful if you are looking at buying a used set. I have both 8-19mm(early 2000's) and 3/8"-7/8"(early 2000's) but they are USA made. They are, to my eye, identical to the current OEX line of Snap-on's. I compared them side by side, one on top of the other. They lack the polishing and finishing of a Snap-on, and have a dull Chrome finish. I'm thinking the Blue Point wrench COO switched to Taiwan around 2003 or 2004.
If you're looking at a used set and want USA made, they will be stamped so directly on the beam next to the Blue Point name and part #.
I can't speak about the current Blue Point stuff. I'm with caper on this.......why pay the money for imported Blue Point when you can find the same for cheaper?