Pharaoh was a title, somewhat equivalent to a king, as used by the Human population of ancient Egypt.
History and specifics[]
One pharoah was Ramses II (TOS episode: "Patterns of Force") and another was Ramses III. (TOS novel: Strangers from the Sky)
The pharaohs were mummified in a ritualistic manner after death. (DS9 novel: Station Rage)
In an alternate reality, the vizier of one Egyptian pharaoh was secretly an escaped alien criminal. Tracking the alien down, the Doctor, Amy Pond and Rory Williams made their way through the Pharoah's palace and confronted the disguised alien vizier in the throne-room. The alien was recaptured by the Doctor and the pharoah later assisted the Doctor in finding his TARDIS. (TNG - Assimilation² comic: "Issue 1")
In an alternate timeline, the USS Defiant was sent back in time to what Admiral Nechayev thought of as the time of the pharaohs. (DS9 novel: Time's Enemy)