Slavery was massive in Southeast Asia (SEA) as far back as we can tell. There were slaves in practically every sector of the economy. Slavery was so widespread in SEA that even the slaves had slaves. To give just one example of the scale we are talking about, an inscription of Jayavarman VII of Angkor from about 1200AD records the king’s donation of 306,372 slaves to religious foundations.

Slavery in SEA is impossible to cover in depth in a short post. It varied between time periods and area. There were also nuanced distinctions between bondsmen, dependents and slaves. I’ll try to give an overview here, and I will include examples from maritime SEA as well as mainland SEA as I am more familiar with the former than the latter.

HOW DID ONE BECOME A SLAVE?

SLAVE RAIDING: As you mention, SEA had a very low population density, so manpower was a valuable resource. Raids for the express purpose of taking people hostage were common. Raid victims were usually held for ransom, and it was common for villages to have a 'ransom fund' as a kind of insurance that was used to redeem hostages. Hostages that were not redeemed for whatever reason ended up either being sold as slaves, or working as a slave for the raiders. In general, it was societies of wet rice cultivators (those that had fixed plots of farmland) that raided societies of swidden farmers (societies that sustained themselves through shifting cultivation).

WAR: The enslavement and transfer of enormous numbers of rival populations featured prominently in SEA wars. During the wars of Sultan Iskandar Muda of Aceh, for example, the Sultan is said to have carried off 11,000 people from Pahang in 1618 and 7,000 from Kedah in 1619. Slaves might also be provided to a victorious kingdom as a condition of peace. Labour was welcome as there was no end of duties that required muscle power - digging and maintaining canals, cleaning the streets and so forth. However, it was skilled labour that was especially prized, and we have records of artisans, chefs and blacksmiths being forced to settle in the victor’s capital so the victorious king could use their skills. Take, for example, this paragraph from the Pongsawadan Yonok (The Northern Thai Chronicle) describing a Thai king’s victory over Burma in the 13th century:

[Northern Thai King] Mangrai led his army to [Burmese] Pagan and camped to the southeast… The [Burmese] king sent his mission with gifts for presentation to Mangrai to show his submission. Mangrai then asked him to provide him with two skillful gong-smiths and other smiths of skills requested. Mangrai returned to [his capital] Muang Kumkhan leaving gong-smiths in [his vassal states of] Chentung, Chiengsaen and other kinds of craftsmen at Kumkhan. The arts and crafts were then spread over the land of Lanna [northern Thailand]...

In the 16th century, the process was repeated but in reverse. The Burmese chronicle Hmannan Yazawin Dawgyi (The Glass Palace Chronicles) describes how, having conquered the Thai kingdom of Chiang Mai in 1558, the Burmese king

… sent whole families of skilled artisans and handicraftsmen, such as painters, lathe workers, gold and silversmiths, blacksmiths, bronze workers, masons, lacquer workers, dyers, embroiderers, perfumers and also men skilled in the training and care of elephants and ponies, as well as those skilled in the culinary art, to Hanthawaddy [the Burmese capital] and made them settle down there.

By the 18th century, it is estimated that 35% of workers employed by the Burmese king were from captured foreign populations. By the early 19th century, an estimated 20% of the entire population of upper Burma was composed of captured foreigners and their descendants.

VASSALAGE AND OBLIGATION: Historians have remarked that SEAsian society in general seems to have been built on obligations to whoever was one level above, and very often, labour was one of those obligations. For example, if you were a villager, you might owe a certain number of days of unpaid labour to your village chief. Your village chief, in turn, probably owed a certain number of days of unpaid labour to whoever was above him, perhaps a fellow village chief he had sworn loyalty to because he was especially impressive. That village chief might in turn owe labour to the sultan, who in turn owed labour to his overlord sultan. Of course, the sultan himself wouldn’t go and work for his overlord, the actual labouring would be done by the villagers at the bottom of the pyramid, but that labour would be deducted from their obligations to their village chief. This was also a common condition of vassalage. This could be classed as ‘part-time slavery’, as even if a labourer was free for the rest of the year, when he was called up to provide labour, he was certainly labouring under slave-like conditions with no payment and no way of saying ‘no’.

DEBT BONDAGE: People selling themselves (or, less commonly, their family members) into slavery in return for capital was very common in SEA. In 18th and 19th century central Thailand, debt slaves made up about half of the total population. George Alexander Wilken, a civil servant of the Dutch colonial government, describes how Toba-Bataks on Sumatra who wanted to gamble on market day would go equipped with a special rope, the tali pasa, as a sign that their bodies were the surety for their gambling debts. Other SEAsians might seek to raise capital for those two great expenses in SEA society - weddings and funerals. During times of hardship, it was also common for SEAsians to sell themselves into slavery, where their basic needs would be met. A debt slave’s labour did NOT cancel out his debt. His labour was considered payment for the interest on the debt, and the debt still had to be paid in full, in cash. Naturally, if it were that easy to make that sum of money nobody would be selling themselves into slavery in the first place, so if a debt slave died without paying off the debt, the debt was passed to his children, who would in turn become slaves to the same master.

LEGAL INFRACTIONS: Enslavement to the royal court was a class of punishment by itself. In Cirebon on Java in the 1700s, those convicted of serious crimes were considered durjana and sentenced to death. Those convicted of lesser crimes were pradah. The punishment for a pradah was either a term of enslavement or a fine, and if he could not pay the fine he would also be enslaved.

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