The Swiss claim that the French usurped the name from the region of Gruyère. Not so, say the French. In the Middle Ages, an officer of the French government called a “gruyer” presided over forest lands and collected taxes — in the form of cheese. It is this gruyer that their cheese is named after, claim the French, and they can show tax records that date back to the 1100s to prove it.
However in Roman times the Jura region was the homeland of an ethnic group called the Sequanes and Roman texts dated from 40 B.C. describe the cheese process used in Sequany — which is the same as that used in the making of Gruyère. So if you want to be pedantic Gruyère was acttually invented by the Romans.
After decades of fighting over the name, cheese makers in the Franche-Comté region decided that protecting the name “Gruyère” was hopeless and applied for an appellation under the name “Comté.” Savoy, too, renamed their cheese “Beaufort”. If you have a Gruyère style cheese and do not know its origins then there is one general rule of thumb - French Gruyère-style cheeses must have holes according to French agricultural law, whereas holes are usually not present in Swiss Gruyère.