Isanavarman

Phraya Kalavarnadit, the legendary first king of Lavo, is said to have established the city of Lavo around 450 CE as one of the Dvaravati city-states.

Kalavarnadit establishes a new era called the Chulasakaraj, which is the era used by the Siamese and the Burmese until the nineteenth century.

Isanavarman I of Chenla expands Khmer influence to the Chao Phraya valley through his campaigns around the seventh century.

Dvaravati cities that fall under Khmer hegemony become Lavo, while the Western cities are spared from Khmer hegemony and form the Kingdom of Supannabhum.

Lavo is the center from which Khmer authority rules over Dvaravatians.

The only native language found during early Lavo times is the Mon language.

However, there is debate whether Mon was the sole ethnicity of Lavo.

Nonetheless, it also should be noted that the area also home to a sizable Malays and Khmer people earlier during Dvaravati period.

Some historians point out that Lavo was composed of mixed Mon and Lawa people (a Palaungic people), with the Mons forming the ruling class.

It is also hypothesized that the migration of Tai people into Chao Phraya valley occurred during the time of the Lavo kingdom.