The Zulu three traditional sources of military efficacy: manpower, mobilization, and tactics

From Carnage and Culture by Victor Davis Hanson. Page 313.

Much myth and romance surround the Zulu military, but we can dispense with the popular idea that its warriors fought so well because of enforced sexual celibacy or the use of stimulant drugs—or even that they learned their regimental system and terrifying tactics of envelopment from British or Dutch tradesmen. Zulu men had plenty of sexual outlets before marriage, carried mostly snuff on campaign, only occasionally smoked cannabis, drank a mild beer, and created their method of battle advance entirely from their own experience from decades of defeating tribal warriors. The general idea of military regimentation, perhaps even the knowledge of casting high-quality metal spearheads, may have been derived from observation of early European colonial armies, but the refined system of age-class regiments and attacking in the manner of the buffalo were entirely indigenous developments.

The undeniable Zulu preponderance of power derived from three traditional sources of military efficacy: manpower, mobilization, and tactics. All three were at odds with almost all native African methods of fighting. The conquest of Bantu tribes in southeast Africa under Shaka’s leadership meant that for most of the nineteenth century until the British conquest—during the subsequent reigns of Kings Dingane (1828–40), Mpande (1840–72), and Cetshwayo (1872–79)—the Zulus controlled a population ranging between 250,000 and 500,000 and could muster an army of some 40,000 to 50,000 in some thirty-five impis, many times larger than any force, black or white, that Africa might field.

Unlike most other tribal armies of the bush, the Zulus were no mere horde that fought as an ad hoc throng. They did not stage ritual fights in which customary protocols and missile warfare discouraged lethality. Rather, Zulu impis were reflections of fundamental social mores of the Zulu nation itself, which was a society designed in almost every facet for the continuous acquisition of booty and the need for individual subjects to taste killing firsthand. If the Aztec warrior sought a record of captive-taking to advance his standing, then a Zulu could find little status or the chance to create his own household until he had “washed his spear” in the blood of an enemy.