Kawai Y., with K.F. Friday
Morillo notes that both developments, and the key military changes that marked the late
medieval era, began well before the introduction of Portuguese firearms in 1543 and continued
along virtually the same trajectory before and after that date. The key issue, he argues, was not
the appearance of guns or any other new weapon, but rather the emergence of a level and extent
of political control that made large infantry forces a viable—and then an attractive—alternative
to elite warriors on horseback.
Cavalry, he observes, can be effective in relatively small numbers, while on open ground,
infantry can stand against charging horsemen only when it can form up with sufficient density
and depth to force horses to refuse to collide with it, and only when it has sufficient morale and
courage to stand and face the terrifying charge. This, says Morillo, requires that infantry units
have both ample numbers and enough practice and experience fighting together to be able to
trust their fellows to stand with them, rather than break and run. Effective infantry can, there-
fore, be deployed only by a command authority strong enough to gather sufficient troops, and
rich enough to maintain them while they train or fight together long enough to develop the
needed unit cohesion. Early medieval Japanese commanders, he says, lacked the wherewithal to
accomplish this, but by the sengoku era, they had acquired the political and economic resources
necessary to draft and drill large units of infantry. At this point, infantry became more cost-
effective than cavalry, with ensuing consequences for the composition of armies and the manner
in which battles and campaigns were waged.^49
A decade later, Conlan expanded on Morillo’s argument. Surviving records, he notes, reveal
little or no modification of battle tactics during the period between the Nanbokuchō wars and
the outbreak of the Ōnin War in 1467. Nevertheless, enhanced ability to collect revenue and
more integrated political control over vassal warriors equipped emerging lords with semi-
permanent armies that were—potentially—capable of functioning as cohesive units on the
battlefield. Then, Conlan asserts, the tactical stalemate that ensued after the opening clashes of
the Ōnin War led commanders to the (almost accidental) discovery that well- disciplined infantry
equipped with spears could readily hold their ground against horsemen. Henceforth, the roles of
cavalry and foot soldiers became reversed, with mounted warriors increasingly relegated to
scouting, raids on supply lines, and support of infantry formations, which now served as the
mainstay of military forces.
Similarly, he relates, firearms in and of themselves brought no revolutionary changes to Jap-
anese warfare. They had, in fact, been introduced to Japan, from China via the Ryūkyū islands,
as early as 1466, and records of their use in battle date back to at least the 1520s, although they
did not really catch on until the arrival of the Portuguese harquebus in the 1540s. Even then, he
contends, their diffusion was gradual and their influence on the nature of battles minimal, largely
because while they offered marginally better range and stopping power over arrows, they were
both expensive and insufficient (on their own) to break charges by horsemen or spear- wielding
foot soldiers. The primary contribution of firearms, he concludes, was to give daimyō who could
afford them—principally those in western Japan and the capital region—a slight advantage over
less wealthy eastern rivals.^50
Friday emphasizes changing strategic objectives, brought about by the steady devolution of
political power from the capital to the countryside, as the impetus for tactical evolution.
Throughout the early medieval era, he contends, the central objectives of warfare remained
human, rather than geographic: in function, Heian and Kamakura warriors were more constables
or sheriffs than soldiers or warlords. But the daimyō of the late fifteenth and sixteenth centuries
ruled nearly autonomous satrapies whose borders coincided with the area that they—and the
lesser warriors whose loyalties they commanded—could dominate by force. This dramatic
change in political circumstance, he argues, drove a shift in the underlying purpose of war, as the