The Sultan of Kelantan’s Birthday is observed in Malaysia on September 29, marking the official birthday of the Sultan, who is the constitutional head of state in the region. This public holiday is celebrated for two days, on September 29 and 30, throughout all states in Malaysia. The history of Kelantan dates back to the 13th century, with the first Sultan, Muhammad I, ascending to power in 1800. The Sultanate has experienced various political changes, including periods of vassalage to Siam and British protection. As of 2023, the current Sultan is Muhammad V, who was proclaimed the 29th Sultan in 2010. The celebration of the Sultan's birthday serves to maintain a consistent date for public festivities, even as new rulers ascend to the throne.