Za

Za was the leader of a primitive tribe circa 100,000 BC. To preserve their power and authority, the tribal leaders kept a monopoly on the secret of making fire. The secret and leadership was passed down from father to son. Unfortunately, Za's father was killed during a hunt before he could pass on the secret. Unable to make fire for his people, Za found his leadership in jeopardy, more so with Kal, an outsider taken in by the tribe, hoping to take over.

Za's fears seemed confirmed once Kal had captured the First Doctor, claiming that he had seen the old man make fire. Za ordered the stranger and his three companions imprisoned in the Cave of Skulls, hoping to wrest the secret of fire from them before Kal could and so stay in power. The strangers escaped, Za pursuing them together with his mate Hur.

Za was attacked by a forest animal. The Doctor and his friends tended to his wounds and took him back to the tribe.

Despite this, Za still had the strangers reimprisoned. Even after they taught him the secret of fire and helped him defeat the would-be usurper Kal, Za still refused to release them.

Eventually the strangers managed to escape again, and when Za led the tribe in pursuit of them, he saw the strangers enter the Doctor's TARDIS, which vanished.

Biography from the TARDIS Data Core article, licensed under CC-BY-SA