Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Yamtuan Besar, also known as Yang di-Pertuan Besar, is the royal title of the ruler of the Malaysian state of Negeri Sembilan. The ruler of Negri Sembilan is selected by a council of ruling chiefs in the state, or the datuk-datuk undang. This royal practice has been followed since 1773. The Yamtuan Besar is selected from among the four leading princes of Negeri Sembilan (Putera Yang Empat). This unique form of government later inspired the first Prime Minister of Malaysia, Tunku Abdul Rahman, to implement a form of rotational constitutional monarchy for a newly independent Malaya. Thus, the office of Yang di-Pertuan Agong was created. Negeri Sembilan has been receiving immigrants from Sumatra for hundreds of years. Prior to the implementation of this unique form of monarchy, the area was ruled by the Sultan of Malacca. After Malacca was defeated by the Portuguese, it was ruled by the Sultanate of Johor.