The Lycian people inhabited the southwestern coastal part of ancient Anatolia, first mentioned in records of the Hittite Empire as Lukka. After the fall of the Hittite Empire, they emerged into historical records as a separate nation in the 8th century BCE.
The language of the Lycians belonged to the Anatolian branch of Indo-European, and was related to Lydian, Carian, Phrygian, Hittite, and most closely to Luwian. In fact, it is so closely related Luwian that it is very likely that the Lycian language evolved from Luwian.
The Lycians adopted an early form of the Greek alphabet to write their language. However, the Lycian language had sounds that were not in Greek, and thus the Greek alphabet was insufficient to fully reproduce the Lycian language. As such, additional letters were introduced to represent these sounds. The origin of these letters are in some debate, some scholars proposing a Cypriot origin while others positing borrowings from Carian.
The following is the Lycian script.
The red text above represent the transliteration of the Lycian letters. Note that ã and ẽ are nasalized vowels, meaning that the vowels are pronounced with a resonance in the sinus cavity. More interestingly, m̃ and ñ appear to be syllabic nasals, or nasal consonants (such as [m] and [n]) that function as vowels.
By the 3rd century BCE the Hellenistic world created by Alexander the Great's empire assimilated many of the nations in its domain, and the Lycians replaced their own culture with the Hellenistic culture, and their language with Greek. Hence, the Lycian script ceased to be used at the close of the 3rd century BCE.