King Asoka

Chandragupta was the father Bimbisara.

He established the North Indian Territory.

Bimbisara

Three sons of different mothers

Eldest Susima

Youngest Tusia

Asoka was the second. 

He was a warrior from young age.

Captured Taxila.

Later Udeni

He fought his brothers and became the King.

Married Devi from the Maurian clan who was Buddhist.

Chakravathi or Kings of Kings was the model then.

Kalinga was a brutal battle.

Instead of being victorious he repented on the carnage that ensued.

The horror and remose made him to change for ever. Educated and very sensitive Asoka sworn not to bear arms again.

Conquer the world through Dhamma was his ultimate message to the world.

He studied Buddhism.

His guru was Bhikku Gupta.

He was accepted to the the Sasana.

He erected Edits all over India.

Law and Order was his message to the people not dictatorial control.

Right not Might was his Goal.

He was pious but was a forceful emperor.

Benevolence to all living beings was his mantra. Sacrifice of animals for food was his name.

Third Buddhist Council was held in Pataliputra.

He sent missions to all over the world including Greece. The name Yona is Greek word for Buddhist converts.

Asoka

Mahinda

Singamitta 

Monks Sona and Uttara were sent by King Asoka from Magada to ? Thailand.

Thai people were originally from China. They move out due to oppression by Chinese Huang King.

They finally reached Thailand.

Thai means to be FREE.

Buddhism came in 1500 after Buddha.

Swarnabhmi

?Cambodia 

?Myanmar 

?Laos

?Thailand

King Kaniska

Mahayana Buddhism reached Sumatra.

But most likely Buddhism reached Thailand from Ceylon.

Therrvara Buddhism was established by Buddhist monks from Ceylon.

Upali and Ariyamuni Theras of Thailand reestablished Buddhist Sangha, Siyam Nikaya in Ceylon in 1753.during King Keerthi Sri Rajasingha. Then, the Buddhism in Ceylon had declined without any Upasampada Bhikkus.

In Thailand King has to be  Buddhist.

Last hereditary King became a dictator and was ousted by a military commander.

The current Kingship was created by this military commander who was devout Buddhist.

Thai people are very disciplined and respect their military. The military never allowed foreign conquer for many centuries.

Thai follow strict Theravada Buddhism.