Here we would contrast slavery in the New World and ANE slavery in general:
Entry: In
Islamic and
Transatlantic slave trades, slavery was overwhelmingly involuntary: people were captured by force and sold - or at times (such as in the case of the Atlantic trade), people - often fellow Africans - would sell their captives or prisoners of war to European buyers.
In the ANE, the opposite was the case: slavery was a voluntary act. The impoverished would either sell themselves, or their relatives, in return for economic security and protection. And many of the documents that survive today actually emphasize that the transaction is voluntary, which applies not only to self-sale but also to those who are the object of sale (though admittedly the consent was sometimes fictional).
War was not a major source of ‘real’ slaves, despite the large number of war captives in every battle. The great majority were not turned into slaves (only a small percentage), but rather were settled on the land as palace and temple serfs. The question would naturally arise: why is this the case? Slavery was the optimal form of dependence, and very often there was no shortage of prisoners captured in war. Besides, there were no legal or ethical norms preventing these prisoners from being turned into slaves. But this happened in a negligible percentage of cases, while the overwhelming majority were settled in places specially set aside for them, paid royal taxes, and carried out obligations, including military service.
The same holds true for the Israelite case: even in wars on foreign soil (Deuteronomy 20:10-11), if a city surrendered, it became a vassal state to Israel, with the population becoming serfs (
mas) who had to perform
corvée labor, not slaves (
'ebed,
'amah).
Motive: In the New World, slavery was motivated by the economic advantage of the elite. The plantation economies of the New World were in fact built on slave labor. Seventy percent of the enslaved people brought to the new world were used to produce sugar, the most labor-intensive crop. The rest were employed harvesting coffee, cotton, and tobacco, and in some cases in mining.
In the ANE, the dominant (statistically) motivation was economic relief of poverty - ‘slavery’ was initiated by the slave, not by the owner - and the primary uses were purely domestic (except in cases of State slavery, where individuals were used for building projects). The two-volume work
[A History of Ancient Near Eastern Law](A History of Ancient Near Eastern Law) (2003) surveys every legal document from the ANE (by period) and includes sections on slavery:
Most slaves owned by Assyrians in Assur and in Anatolia seem to have been (originally) debt slaves - free persons sold into slavery by a parent, a husband, an elder sister, or by themselves. (1.449)
Sales of wives, children, relatives, or oneself, due to financial duress, are a recurrent feature of the
Nuzi socio-economic scene…A somewhat different case is that of male and female foreigners, called
hapiru (immigrants) who gave themselves in slavery to private individuals or the palace administration. Poverty was the cause of these agreements… (1.585)
Most of the recorded cases of entry of free persons into slavery [in
http://en.wikipedia.org/wiki/Emar”]Emar] are by reason of debt or famine or both…A common practice was for a financier to pay off the various creditors in return for the debtor becoming his slave. (1.664f)
On the other hand, mention is made of free people who are sold into slavery as a result of the famine conditions and the critical economic situation of the populations [Canaan]. Sons and daughters are sold for provisions… (1.741)
The most frequently mentioned method of enslavement [Neo-Sumerian,
http://en.wikipedia.org/wiki/Ur_III”]UR III] was sale of children by their parents. Most are women, evidently widows, selling a daughter; in one instance a mother and grandmother sell a boy … There are also examples of self sale. All these case clearly arose from poverty; it is not stated, however, whether debt was specifically at issue. (1.199)