Thailand has been occupied for thousands of years, but there weren’t many people living here until the population exploded in the 20th century. For thousands of years, Thailand was mostly forest and wild animals. In 1900, 85% of the land was deep forest. Since 1960, Thailand has lost 80% of that forest. If you want an explanation for the flooding problem, that’s it in a nutshell.
There were two kinds of monks in Thailand, temple-bound monks, mainly in Bangkok, and forest monks, who wandered about, often living in huts in the forest, or in caves. Two temple monks from Isaan (a five week journey away) described their first visit to Bangkok in 1905. They said it was an uncrowded city, and in order to relieve oneself, one need only step into the forest to do so. The canals were full of water pure enough to bathe in and to drink!
This is a thoroughly Buddhist country. And everywhere you go, especially in Chiang Mai, you find a temple, or a ruined temple. The picture above is a tunnel in Wat Umong, the forest temple, near my house in Chiang Mai.