Originally founded in the 1930's by Mitsuo Matsuki and Atsuo Kaneko, (who later helped found Teisco), making Guitars branded Guya for the Japanese market. Production stopped for WWII and after the war Matsuki started up again founding first the Tokyo Sound Co. and in 1956 founded Guyatone. They were the first Japanese manufacturer to sell their own brand named instruments to the American public, but the were also heavily involved in the Japanese OEM production of the 60's and 70's, producing a lot of different brands of Guitar certainly, for a lot of different people, (It's much harder to say about the Ukuleles and most information is only about the Guitars. It is possible they never made any Ukuleles but there are some brands that they are down as the only producer of?) In 1995 Mitsuo Matsuki died and in 2013 Guyatone separated from Tokyo Sound Co. to become an independent firm mainly making Guitar effects pedals.

When they were doing the OEM work they produced instruments branded Antoria, Barclay, Broadway, Canora, Coronado, Crestwood, Delta, Futurama, Guyatone, Howard, Hi-Lo, Ibanez, Ideal, Imperial, Johnny Guitar, Kent, Kingston, Lafayette, Lake, Maxwell, Montclair, Omega, Orpheus, Prestige, Royalist, Saturn, Silhouette, Silvertone, Vernon, Winston, Zenta and probably produced Beeton, Bradford and Regent. This may not be all the brands they made, I haven't seen all of these names on Ukuleles and they may not have been the only firm producing them?