Who was the last pharaoh of ancient Egypt?

Cleopatra VII was the last pharaoh, ending the Ptolemaic dynasty founded by one of Alexander the Great's generals after his death. That makes her Macedonian Greek by descent rather than Egyptian, ruling a country her family had governed for nearly three centuries while mostly declining to learn its language; she was a notable exception in speaking Egyptian herself. Her reign was dominated by the problem of Rome, which by then could make or unmake rulers in the eastern Mediterranean, and she handled it by allying personally and politically with the most powerful Romans available, first Julius Caesar and then Mark Antony. When Antony lost the naval battle of Actium to Octavian in 31 BC, the strategy collapsed. Both died the following year, and Egypt was annexed as a Roman province governed directly by the emperor, ending three thousand years of rule by pharaohs.

Egypt became Rome's chief grain supplier, which is why emperors kept the province under unusually tight personal control.