Boker is what would happen if Spyderco branded their knives based more around factories of origin and all the different divisions. They also have a freakishly big catalogue, sort of like Spyderco. The Boker M4 Sherman-Damast looks very cool.
Boker Solingen, with a tree logo, is a mark for Made in Germany. There's also
Boker Manufactur and I'm still not 100% what the deal is there.
Boker Arbolito are made in Argentina. I haven't gotten around to buying any of their fixed blades yet, but they look nice and at some point I'll probably get at least one. If it's a Arbolito folder it's made in China, because their factory don't make folders.
Boker Plus is made in Europe, the US (via FOX Cutlery), and Asia. There seems to be have been a definite shift in the Boker Plus knives to move production to China for most models. There are still 11 Boker Plus knives made in the US, 1 super expensive Italian Boker Plus with M390 steel, 36 made in Taiwan, but the vast majority made in China. Other than the real high speed Italian model, the Chinese made ones (especially those not made from 440 steel) seem to be the best of the Boker Plus division (other than the Cop Tool that is made in Taiwan). I've seen a few Boker Plus knives that used to be made in Europe now made in China, like the Pro Pry.
Boker Magnum are the bargain bin that run the gamut from gas station knives to all right beaters, mostly made with Chinese 440 steel. It's kind of strange to have your bargain bin knife division called "
Magnum".
There's also Boker: Manly (Bulgaria), Old Bear (Italy), Higo (China), and probably half a dozen other divisions out there. It's a bit like trying to figure out what Nestle owns.