History: The Autthayan period, 1351-1767 whereas Sukhothai was an independent kingdom for only about 200 years, its successor, Ayutthaya situated in the rich rice plains of the Chao Phraya River basin, about 55 Bangkok- lasted more than 400 years. During the miles north of present-day Ayutthayan period the Tai consolidated their position as the leading power inwhat is now central and north-central Thailand, as well as throughout much ofits southern neighbours called the country"Siam, or a peninsular region. Since many of Ayutthaya's name similar to it, the Tai of Ayutthaya came to be known as the Siamese