228 SOCIAL REFORMrank. The demand for soldiers led to the watering down of the qualifications:
special red warrants (llOngp ae) manumitting slaves or admitting them to higher
examinations were distributed to provincial officials who would supposedly hand
them out to slaves after counting enemy heads. The system was easily corrupted:
slaves turned in the heads of ordinary Korean vagrants or beggars who died of
natural causes, and officials sold the red warrants. These measures met with stiff
opposition, and some restrictions were imposed to limit the number of manu-
mitted private slaves. The examinations were suspended once, and then dropped
altogether sometime soon after the war, probably in the early seventeenth cen-
tury. And yet it is likely that twenty to thirty thousand slaves gained commoner
status during the period by this means.8l
One of the most significant changes was the open recruitment of slaves into
regimental units of regular commoner soldiers, but a concession was made to
conventional prejudice by keeping units with slave soldiers (sog 'ogun) separate
from those with commoners alone. Slaves were also brought into the new Mil-
itary Training Agency in 1593 to serve alongside yangban and commoners, but
because runaway slaves were using the agency as a refuge, King Sonja decided
to prohibit the recruitment of private slaves for the agency in 1603. Nonethe-
less, private slaves remained as part of the military service system, as duty sol-
diers in the sog'o units in the provincial garrisons and abyong (ivory troops) who
functioned as aides to provincial governors or military commanders, or as sup-
port taxpayers for those duty soldiers. In 161 I, the minister of rites remarked
that most of the commoners serving in the 200,000-man sog'ogun had bought
their way out of service, leaving only poor commoners and slaves. In 17 I 4 King
Sukchong expanded the opportunities for both official and private slaves to sub-
stitute for commoners on military service, and by the 1720S most of the sog i)
soldiers were slaves.x2
Manumission by Purchase
Another important effect of the Japanese and Manchu invasions was a signifi-
cant increase in the purchase of freedom by slaves. The practice, referred to as
the grain contribution (napsok), was allowed as early as 1485 when the slave
Tm Pok was reluctantly allowed to purchase the freedom of his four sons for a
contribution of 750 sam of grain for famine relief, but few slaves could have
afforded such a large sum. In 1553, another famine year, the price for manu-
mission had dropped to a smaller but still considerable figure, 50-I 00 sam, but
in 1583 after the crisis had passed, the bureaucrats persuaded the king to pro-
hibit the practice.
During Hideyoshi's invasions in 1592 slaves were able to gain exemption from
service for a contribution of 100 sam and manumission from slavery for 500 sam
or more, still rather expensive prices, but for the first time the state avoided com-
pensation of the owners. Under the pressure of war the system was liberalized
further; manumitted slaves could purchase rank or office as well, and officials