The golden age of Islam in the region is when Malacca became an Islamic sultanate. Many elements of Islamic law, including political and administrative sciences are incorporated into Malacca law, especially the "Udang-Undang Melaka" (Law of Melaka). The ruler of Melaka received the title 'Sultan' and was responsible for Islam in his kingdom. In the 15th century, Islam spread and developed throughout the Melaka region including the entire Malay Peninsula, Riau Islands, Bintan, Lingga and several areas on the eastern coast of Sumatra, namely Jambi, Bengkalis, Siak, Rokan, Indragiri, Kampar, and Kuantan. Malacca is considered a catalyst in the expansion of Islam into other areas such as Palembang, Sumatra, Patani in southern Thailand, North Kalimantan, Brunei and Mindanao.