In Bangkok, the Thai script printed on street signs is a direct descendant of the Pallava script that developed in southern India between the 4th and 6th centuries CE. In Phnom Penh, the Khmer script can be traced back to the same ancestor. The same applies to the Burmese script in Mandalay and the Lao script in Vientiane.
Four different writing systems, one common origin in the Indian subcontinent. None of them arrived through armies crossing the Bay of Bengal.
Ancient India never militarily colonized Southeast Asia. Yet between the 3rd and 13th centuries CE, Brahmi-based writing systems spread from southern Vietnam to the Philippine archipelago. The Khmer, Thai, Lao, Burmese, Mon, Kawi (Old Javanese), Balinese, and Philippine Baybayin scripts all originated from the same family tree.
The Script That Came from Southern India
The origin of all these writing systems was the Brahmi script, which is believed to have existed in the Indian subcontinent around 450 to 350 BCE, with the earliest archaeological evidence found in Anuradhapura, Sri Lanka.
Emperor Ashoka (268 to 232 BCE) used Brahmi to carve his edicts throughout his empire, giving the script a reach that extended beyond the borders of a single kingdom.
From Brahmi, one southern branch developed into the Pallava script between the 4th and 6th centuries CE in what is now southern India.
The Pallava script was later used to copy Buddhist and Hindu religious texts, as well as royal inscriptions by rulers who wished to demonstrate their connection to the Sanskrit literary tradition, the scholarly language recognized across kingdoms in Asia.
Within the maritime trade networks of the Bay of Bengal, which had already been active since the early centuries CE, the script traveled alongside merchants and monks crossing the sea.
3rd Century: The Earliest Evidence on the Coast of Vietnam
The earliest physical evidence of this script family in Southeast Asia was discovered near Nha Trang in southern Vietnam: the Vo Canh inscription, written in Sanskrit using an early Brahmi script.
Believed to date from the 3rd century CE, the inscription is the oldest Sanskrit inscription in Southeast Asia and is now recognized as a National Heritage site.
The presence of a Sanskrit inscription at this location was not a sudden event. Historian George Coèdès, in The Indianized States of Southeast Asia (1968), documented how maritime trade networks connecting southern India and Southeast Asia had already been active long before the inscription was carved.
Merchants and monks were the primary carriers of writing systems and religious texts across the Bay of Bengal, not military expeditions.
4th to 5th Centuries: Kings Who Chose Sanskrit
One century after the Vo Canh inscription, the same script appeared in a more surprising location: seven stone monuments in Kutai, East Kalimantan, Indonesia.
Believed to date from the 4th century CE, these Yupa inscriptions were written in Sanskrit using the Pallava script and record religious ceremonies held by King Mulawarman, making them the oldest written evidence in the Indonesian archipelago.
What most clearly reveals how this script spread is the sequence of the kings' names. The first generation was named Kundungga, a local name rather than a Sanskrit one. His son was named Aswawarman. His grandson, Mulawarman, had fully adopted a Sanskrit-based name.
The change took place over three generations, not because of external coercion, but because each successive generation chose to adopt it more deeply. Research compiled by ANU Press describes this pattern as evidence that Southeast Asian rulers were active agents in the process of adoption, rather than passive recipients.
One century later, another inscription appeared in West Java: the Ciaruteun inscription. Discovered on the banks of the Ciaruteun River near Bogor and believed to date from the 5th century CE, it was written in the Pallava script using the Sanskrit anustubh poetic meter.
The inscription mentions King Purnawarman of Tarumanagara and compares his footprints carved into the stone with the footprints of a god. Two centuries after the Vo Canh inscription, a king in Java was already composing Sanskrit poetry in the correct meter.
1283: When a Borrowed Script Was Adapted for a Tonal Language
Between the 7th and 13th centuries, the Pallava script continued to develop on mainland Southeast Asia and evolved into the Khmer script in Cambodia, which later spread to neighboring kingdoms.
When King Ramkhamhaeng of the Sukhothai Kingdom created the Thai script in 1283 CE, he based it on the Old Khmer script, which had already inherited the Pallava tradition. However, he did not copy it unchanged.
The technical challenge was that Sanskrit, Pali, and Khmer are not tonal languages. Thai has five tones that distinguish the meanings of words.
As a result, Ramkhamhaeng added tone markers that did not exist in the earlier Khmer script, a deliberate modification to accommodate linguistic needs that the parent script had not anticipated.
The pattern was the same as what had already been seen in Kutai seven centuries earlier. The script arrived through trade networks, then was adapted by local rulers to meet the specific needs of their own language.
The stone inscription recording the creation of the Thai script, known as the Ramkhamhaeng Inscription, is still preserved at the National Museum in Bangkok.
