510 MILITARY REFORMConcentration of Frontier ForcesYu Hyongwon cited a number of Chinese sources to justify an argument against
the excessive fi-agmentation of military forces on the Korean frontier. au-yang
Hsiu of the Sung, for example, had complained that in his own time frontier forces
were too finely subdivided into small, walled-town garrisons, and strategic defen-
sive positions were staffed by only a few soldiers. He argued that these small
garrisons were too weak to defend against a concentrated force of invaders?2
Ch'iu Chiin made virtually the same remarks for the Ming. In the early Ming
dynasty (during the Hung-wu and Yung-lo eras, 1368-98, 1402-24), the troops
on the frontier were able to defend a border that was much longer than in Sung
times because troops were concentrated in a few strategic places. By the Cheng-
Cung era (1436-49), however, the mistake was made of dividing up frontier troops
into a number of small redoubts, repeating the mistake warned against by Ou-
yang Hsiu of the Sung.^21Weaknesses of the Chin'gwan SystemYu also believed that a hierarchical organization of provincial bases backed up
by local troops under district magistrates was also necessary. His thinking on
this question was heavily influenced by Yu Songnyong's proposal offered ini-
tially in 1591 just prior to Hideyoshi's invasion, and with greater force in 1594
during the period of armistice, to establish a phalanx of local garrisons that would
enable multilayered lines of defense against an invading enemy.24
The essence of the system was decentralized command and responsibility.
Commanders would be given authority to train their troops in peacetime, and
in wartime to organize the troops, form them into units, and defend the territory
under their charge. The area under the jurisdiction of the chin 'gwan would con-
sist of several civil districts so that it could mobilize a force sufficiently large
to resist an invader. 2SYet one wonders how efficacious this plan would have been
had it been tried against Hideyoshi. Hideyoshi's initial landing force at Pusan
in 1592 was 18,000 troops, but five days later there were 40,000 Japanese on
Korean soil, and by the end of the next month, 156,000.^20 It is doubtful that even
a large garrison under the chin' gW(l11 system could have held out against such
superior numbers without the assistance of divisions of mobile reserve forces.
Both Yu Songnyong and Yu Hyongwon probably misunderstood the true nature
of the chin 'gwan system adopted under Sejo in the mid-fifteenth century.
Although this system established a hierarchy of command in three tiers of gar-
risons and called for distribution of army bases in the interior and naval bases
along the coast, the fundamental principle of organization was that the civil dis-
trict magistrate would assume military responsibilities for the defense of his own
walled town. On paper, one could draw a diagram that might suggest the capac-
ity oflarge inland bases to mobilize the troops of the subordinate garrisons under
their command, but in fact the troops of each inland garrison were drawn from