Si Kottaboon

While the Dvaravatians ruled Chao Phraya, Isan was the place of the Si Kottaboon culture, which belonged to the native Mon-Khmer people. Si Kottaboon is regarded as a stem culture of Dvaravati with Mon scripts and oval-shaped cities. The Thammachakras of Dvaravati became the Semas or Stone Leaves of Si Kottaboon. The culture tolerated the Khmer Chenla expansions around the 7th century. The southeasternmost part of Isan was the heartland of the Chenla kingdom that expanded over the southern Funan around the 7th century