At the mouth of the Tigris, he was able to lighten his load. Where the Dur-Ellil canal meets the eastern edge of the river estuary, the Persian kings had founded a royal garrison two hundred years before and stocked it with Carian settlers, fellow countrymen of Scylax the sea captain and thus well suited to naval work on the Persian Gulf. The garrison had fallen into disrepair and Alexander felt inclined to replace it; now that Nearchus had explored the Persian Gulf, a city at the mouth of the Tigris could resume the Carian sailors' duties and serve as the port for India's shipping and traders. The descendants of the Carians' garrison were recruited as settlers and combined with as many army veterans as could decently be shed. Once again, an Alexandria took its cue from an ancient oriental outpost, and again it would live up to its founder's hopes. The new Alexandria lasted barely a hundred years before being ruined by floods, but the site was twice restored by Greek and Parthian kings and became the main port for near-Asian trade with India, visited by the Roman Emperor Trajan and still maintained by the Arabs a thousand years after Alexander's foundation. Its neat parallelogram of streets and houses, designed as if it were a military camp, has recently been found by an English air survey. Alexandrias, as their founder recognized, were his surest claim on posterity.

Rid, therefore, of a few hundred veterans, Alexander left his new city to be built and sailed up the Tigris, removing weirs and allowing his surveyors to measure the length of the river. At Opis, on the river bend south of modem Baghdad, he paused to meet Hephaistion and the land army. He knew now that there was no escaping his problem. From this point onwards, his route and the veterans' would have to diverge, for it was impossible for boats to sail up the Tigris any further, and at Opis the road system offered an alternative; he could either strike west for Babylon or else follow the great eastern highway into Media and Hamadan. The late summer weather would make Babylon intolerably hot, so like the Persian kings, Alexander opted for a visit to Media and the cool of the hunting-lodges of Hulwan. But if the veterans followed him, they would be doubling back and veering away from home. They had to go west, and at Opis the issue was brought out publicly.

Ever since Susa and the sight of the Successors, the troops had been sullen and discontented. Now Alexander called them together and told them that the aged and infirm were to be discharged and returned to Macedonia; they would be handsomely rewarded 'both to the envy of their friends back home and to the emulation of those who stayed in service'. It was the least well-received suggestion he had ever made. The troops rioted and shouted him down. 'Go on campaigning,' they said are to have told him, 'in the company of your father,' meaning Ammon, not Philip, 'but if you dismiss the veterans, you must dismiss us all.' Other reports differed, as the taunts of mutineers are never recorded with accuracy, but whether or not men had referred to Ammon, their disobedience was curtly treated. Alexander jumped down from his platform attended by his closest officers, and pointed out the trouble-makers whom he wished them to arrest. Thirteen men were seized and marched away to their death: Alexander remounted the platform and launched into one of his powerful speeches. Then he strode away to the royal quarters, where he shut himself in, refusing to see any of his Companions or attend to his personal requirements. Only his intimates were allowed inside. None of his officers is known to have described the mutiny, but there is no mistaking the points at issue. Nobody complained that Alexander had lost his sense of proportion or his ability to rule the empire, yet many officers, even a Hipparch, had sided with the veterans, a rare split between Alexander's commanders and his close friends. They booed him, not because he had led them into Makran or because he was likely to lead them into further battles, but because he was trying to exclude them from the future they knew he still offered. It was not a mutiny of men who wished to go home, for after ten years in Asia, a home in the marches of Upper Macedonia had lost its very few attractions: former hill-shepherds had seen and plundered a vastly richer world and they meant to stay at the top of it. They did not intend to leave it to a corps of oriental Successors and a mixed brigade of Persian Companions, when there were perfectly good Macedonians, or so they felt, to carry on instead. It was a mutiny of men who wanted to stay firmly put; had they lost their faith in Alexander, they could have murdered him the moment he jumped off his platform, bodyguards and all. They did nothing, because they needed him.

But Alexander saw it differently. Many of the men he wished to disband were over sixty, or even seventy, years old; they were often unfit and generally resistant to change. Had he known how they were to return and dominate the battlefields after his death, he might have hesitated, but at Opis, he was thinking of his own future and for that, old men were too short-term a liability. His ambitions would strain Macedonia's manpower, a source on which he had not been able to draw for the past seven years, and it made sense to call on his large oriental reserves to replenish an army which had been humbled by Makran. The province of Persia alone had more fighting men than his father had ever commanded in his new Macedonia, and by recruiting them, he could involve them in the profits and responsibilities of conquest. His weddings at Susa, his Iranian Companions and Successors were proof, to his great credit, that he knew where the loyal governing class of the future should be made to lie. He did not want a court which was recruited exclusively from Macedonians any more than he wanted the equality or the brotherhood of man; he wanted, rightly, to 'draw on the best recruits, whether Greek, Macedonian or barbarian'. There was no better guard against inflaming the national feelings of the peoples he had conquered than to invite their governors to share in his court.

The army had threatened him with what they believed he would never do, but being Alexander, it was not long before he announced that he would do it all the same. They had told him that if any veteran was dismissed they would all desert and leave him to liis new Iranian friends; after an ominous silence from the royal tent, news came that the Iranians were his perfect and sufficient army of the future. There were to be Iranian Shield Bearers, Companions, Foot Companions and Royal Squadrons; the army commands were to be held by picked orientals, who would be treated as the king's equals and therefore allowed the traditional privilege of greeting him by a kiss. For two days after the announcement, Alexander remained in his tent, seen only by his Iranian officers, close Companions and Bodyguards. He was bluffing boldly, but if the troops had been stubborn, he would no doubt have carried on with his design.

With their leaders dead and their wages in danger, the troops hesitated, struck by Alexander's new announcement. It was a very different situation from the mutiny at the Beas. There too, Alexander had threatened to march on without them, but they had known they were indispensable. This time, they had challenged him to disband them and he had shown every sign of being prepared to do so. Many officers heard their rank was passing to Iranians, a hint that they too had sympathized with the mutiny. Alexander's close friends stood against them, and this they could not break. Threatened men, they took fright:

They ran to the royal quarters and threw down their weapons before the doors, as a fervent entreaty to their king; then they stood and began to shout to be allowed inside; they promised they would give up the instigators of the mutiny; they would not depart from the doors, day or night, until Alexander took pity on them.