The Roman domination began in 238 BC and brought Latin to Sardinia, but was often contested by the local Sardinian tribes and proved unable to completely supplant the pre-Latin Sardinian languages, including Punic, which continued to be spoken in the 4th century AD as attested by votive inscriptions. Some obscure Nuragic roots remained unchanged, and in many cases Latin accepted the local roots (like "nur", presumably from Norax, which makes its appearance in nuraghe, "Nurra", "Nurri" and many other toponyms). Barbagia, the mountainous central region of the island, derives its name from the Latin "Barbaria" (a term meaning "Land of the Barbarians", similar in origin to the now antiquated word "Barbary"), because its people refused cultural and linguistic assimilation for a long time: 50% of toponyms of central Sardinia, particularly in the territory of Olzai, are actually not related to any known language. Besides the place names, on the island there are still a few names of plants, animals and geological formations directly traceable to the ancient Nuragic era. Cicero called the Sardinian rebels "latrones mastrucati" ("thieves with rough wool cloaks") to emphasize Roman superiority.