Cybermen

The Cybermen were a "race" of cyberneticallyaugmented humanoids. They varied greatly in design, with different factions originating independently by parallel evolutionon planets throughout time and space,  including Mondas, Telos, an alternate Earth, Planet 14, and Marinus. Some Cybermen were born out of an instinct to survive, others hunger for immortality because their civilisations were dying out and they wanted to survive, and some the intent to upgrade themselves and everyone around them. About 2000 years after the end of the previous Cyberman civilisation, Mondas reached the zenith of its orbit away from Earth. By this time, Mondasian society was similar to that of 20th century Earth. According to one account, the surface of Mondas was inhospitable, meaning that all the Mondasians lived underground. However, the Cult of C'iva were able to survive on the planet's surface. the original doctor met an advance force of Mondans near Snowcap Base in Antarctica. This force was to prepare for Mondas' return to the Sol system and to drain Earth's energy for the Cybermen. Mondas absorbed too much energy and was destroyed, as were the Cybermen on Earth who depended on Mondas for power.
 * early years
 * First meeting the doctor