Philip of Macedon.—Let us briefly recapitulate the tacti cal possibilities thus far evolved, for we are about to enter a period when one man, Philip of Macedon, shook them together, creating perhaps the most perfect tactical instrument ever devised in the history of war. The following lessons had been learnt.
The front of a phalanx of pikemen was inviolable on flat and unobstructed country, consequently the parallel order was ob solete. Its flanks were very vulnerable, consequently the oblique order of Epameinondas offered the best method of attacking heavy infantry with their like. For broken ground, mountain warfare and flank protection, light infantry were essential, and for rapidly outflanking an enemy and attacking him in rear cav alry were the decisive arm. The Persian Wars had taught the Greeks the danger of pitting heavy infantry against cavalry in cavalry country, and the danger of pitting cavalry against light infantry in light infantry coun try. Xenophon who was present at the battle of Cunaxa (q.v.) in 401 B.c. and in virtual command of the io,000 during their famous retreat, produced in his Anabasis and his Cyropaedia the first great treatise on the art of war.
All these things suddenly impinge on the fertile mind of Philip (382-336 B.c.). Out of them he constructed the perfect instru ment—the army of Alexander.
Whether consciously or not, it is not possible to say, he took as his tactical model the body of man and devised his organiza tion accordingly. First he re-armed the phalanx with a longer pike, the Sarissa, and established it as the trunk or stable base of his army ; it was in fact a mobile fortress the front of which defied attack. Having created this defensive base of operations he hinged on to it two arms, the left protective, to ward off blows, and the right offensive to deliver them. Both these arms were composed of cavalry, heavy and light, the right wing being in quality and quantity the stronger. To maintain the maximum flexibility he inserted between these cavalry wings and the pha lanx two joints, or bodies, of light infantry, the Hypaspists on the right and the Thracian Javelin-men on the left. On the outer flank of the right wing cavalry he placed a strong body of light infantry and archers. Finally he organized a staff, a mobile artillery train, a body of en gineers for siege work, and definitely established unity of command in the Macedonian army.
Alexander the Great.— The perfection of this organiza tion, probably the most efficient ever devised to meet the tactical conditions of its day, was fully proved in the campaigns of his son, Alexander the Great, who never lost a battle or a campaign, who invariably defeated his en emy on the plains, in the deserts and in the hills; who was never stopped by a mountain range or a river, and who reduced every fortress he laid siege to. In his four great battles against the Persians and Indians, namely, Grani cus (q.v.) in 334 B.C., Issus (q.v.) in 333 B.c., Gaugamela (q.v.) in 331 B.C. and Hydaspes (q.v.) in 327 B.c., though his grand tactics vary, his minor tactics uniformly are based on the cavalry charge, and spring fully armed and armoured from Philip's superb organ ization, their one aim being to develop mobility through protected offensive action. They may be described as follows.
The tactical idea was to attack the enemy's command, the de cisive point which, in the Persian army, was normally in the centre of the front rank. The method was an attack by cavalry which would roll up or penetrate the enemy's left wing, and so permit of the Persian command being attacked in rear. The pivot of the whole operation was the phalanx, which moved forward towards the enemy's left in echelon with its right leading, the cavalry wings doing likewise. The left being refused enticed the enemy, especially his cavalry, to attack it. The object of the left wing was to draw the enemy towards it ; it was consequently only sufficiently strong to hold its own. Its right was protected by the impenetrable phalanx to which it was hinged by the Thracian light infantry. As the left wing swung back, the right wing, hinged to the phalanx by the Hypaspists, swung forward. The light cavalry fixed the enemy's left wing, and the heavy cavalry forming the apex of an arrow formation (the phalanx in echelon on its left, right leading, and the light infantry in echelon on its right, left leading) struck the enemy a terrific blow, pierced him, wheeled round, charged the enemy's command, and then took the enemy's right wing which was opposed to the Macedonian phalanx, or driving back Alexander's left wing, in reverse. Once destroyed an immediate pursuit followed. Such in brief were the tactics ap plied by Alexander.