FNH (Fabrique Nationale Herstal) was set-up in 1889 by the Herstal guild of firerams makers to manufacture Mauser 1889 under liscence brought by Ludwig Loewe who owner about 50% of the FNH stock. Ludwig Loewe didn't like to see FNH selling the Mauser rifles in competition with themselves in Southern America and around the world, so they imposed strict restriction to the export of the Mauser rifles by the Belgians.
That's why and when Browning came into play, BTW.
Later, Ludwig Loewe carried another contract with FNH to build a quantity of Spanish Mauser 1893 and Brazilian M1894
Then, after WWI, Germany faced restrictions and since FNH were already set-up to build Mauser rifles on a large scale, the started making contracts on M/98 based rifles.
All that to say that FNH was directly involved in the spreading of the original Mauser designs. After WWII, they acquired a lot of machinery and patents from the other plants making Mauser rifles as war reparation.
Starting in 1946, they decided to "modernize" the M-98 for civilian use by removing the military features which ultimately, became the "Supreme" action. So, to determine if the Supreme and later models are clones or "the real thing", one need to know where it came from.
After the '60, FNH sold some of the rights and machinery to Spain and Yougoslavia and then appeared the "Santa Barbara" and "Zastava" "clones" of the "Supreme"....