According to tradition, the Thembu migrated from central Africa along the east coast before settling in KwaZulu-Natal. The earliest known Thembu ancestor is Mbulali, whose grandson (named Thembu), led his people from what became the South African province of KwaZulu-Natal to Dedesi in the present-day Transkei region of South Africa. The Thembu emerged as a unified people during the reign of Ngubengcuka, who united clans living in Thembuland into a single political entity, owing allegiance to the Thembu royal family, or "Hala Mvelase." Famous Thembus include Nelson Mandela, whose father was a reigning nobleman from a junior branch of the Madiba clan of kings, and Walter Sisulu.