Catharese was the written and spoken language of the Cathar. Communication in Catharese included remarking some spoken words with a growl. Cathars were usually also fluent in Basic.[1]
Behind the scenes[]
In Knights of the Old Republic, the Cathar Jedi Juhani speaks Basic, albeit with an accent that includes rolled "r"s and "w"s that sound like "v"s.[2]