Hejaz
Historically, the Hejaz has always seen itself as separate from the rest of Saudi Arabia. The Hejaz is the most populated region in Saudi Arabia; 35% of all Saudis live there. Hejazi Arabic is the most widely spoken dialect in the region. Saudi Hejazis are of ethnically diverse origins.
Old South Arabian
Old South Arabian (or Ṣayhadic or Yemenite) is a group of four closely related extinct languages spoken in the far southern portion of the Arabian Peninsula. There were a number of other Old South Arabian languages (e.g. Awsānian), of which very little evidence has survived, however. A sole surviving Sayhadic language is attested in Jabal Rāziḥ in far north-west of Yemen, though the varieties of speech in neighboring areas have both Arabic and Sayhadic features, and it is difficult to classify them as either Arabic dialects with a Sayhadic substratum, or Sayhadic languages that have been restructured under pressure of Arabic.