Driven by her silver-tipped oars, helped now with the land breeze that swelled her sails, Cleopatra's galley passed astern of the fighting-line on its extreme left, and sixty of the warships of Alexandria followed their queen. Those who watched from the land must have hoped against hope that this was a novel manœuvre, to use the breeze to aid the squadron of their allies to shoot out from behind the main body, gain the flank of the enemy, and then suddenly let the sails flap idly, furl or drop them, and sweep down with full speed of oars on the rear of the attack, with Cleopatra leading like Artemisia at Salamis. But the "serpent of old Nile" had no such ideas. She was in full flight for Alexandria, with her warships escorting her and conveying the wealth that had been embarked when it was decided to put to sea. Was her flight an act of treachery, or the result of panic-stricken alarm at the sight of the battle? But even her enemies never accused her of any lack of personal courage, and there are many indications that it had been arranged before the fleet came out, that, as soon as an opportunity offered, Cleopatra with a sufficient escort should make for Egypt, where several legions were in garrison, and where even if the army now camped beside the Ambracian Gulf could not be extricated from its difficulties, another army might be formed to prolong the war.
But the withdrawal of the sixty ships threw the odds of battle heavily against the rest of Antony's fleet. And matters were made worse by its leader suddenly allowing his infatuation for the Queen of Egypt to sweep away all sense of his duty to his comrades and followers and his honour as a commander. As he saw Cleopatra's sails curving round his line and making for the open sea, he hastily left his flagship, boarded a small and swift galley, and sped after the Egyptians.
Agrippa was too good a leader to weaken his attack on the main body of the enemy by any attempt to interrupt the flight of the Egyptian squadron. When he saw the galley of Antony following it, he guessed who was on board, and detached a few of his triremes in pursuit. Antony was saved from capture only by the rearward ships of the fugitive squadron turning back to engage and delay the pursuers. In this rearguard fight two of the Egyptian warships were captured by Agrippa's cruisers. But meanwhile Antony's galley had run alongside of the royal flagship of the Egyptian fleet, and he had been welcomed on board by Cleopatra.
By this time, however, he had begun to realize the consequences of his flight. Half an hour ago he had stood on the deck of a fighting ship, where comrades who had made his cause their own were doing brave battle against his enemies. Now, while the fight still raged far away astern, he found himself on the deck of a pleasure yacht, glittering with gold and silver, silk and ivory, and with women and slaves forming a circle round the Queen, who greeted him as he trod the carpeted deck. He made only a brief acknowledgment of her welcome, and then turned away and strode forward to the bow, where he sat alone, huddled together, brooding on thoughts of failure and disgrace, while the royal galley and its escort of warships sped southward with oar and sail, and the din of battle died away in the distance, and all sight of it was lost beyond the horizon.
The withdrawal of the Egyptians was a palpable discouragement to all the fleet, but not all were aware that their leader, Antony, had shared Cleopatra's flight. Some of those who realized what had happened gave up all further effort for victory, and leaving the line drove ashore on the sandy beach of Actium, and abandoning their ships joined the spectators from the camp. Others made their way by the strait into the great land-locked haven of the Gulf. But most of the fleet still kept up the fight. The great ships that drifted helplessly, with broken oars, among the agile galleys of Agrippa's Liburnian sailors, or that grounded in the shallows nearer the shore, were, even in their helplessness as ships, formidable floating forts that it was difficult to sink and dangerous to storm. More than one attempt to board was repulsed with loss, the high bulwarks and towers giving an advantage to the large fighting contingents that Antony had embarked. Some of them had drifted together, and were lashed side to side, so that their crews could mutually aid each other, and their archers bring a cross fire on the assailants of their wooden towers. Some ships had been sunk on both sides, and a few of the towered warships of the Eastern fleet had been captured by Agrippa, but at the cost of much loss of life.
To complete the destruction of the Antonian fleet, and secure his victory, Agrippa now adopted means that could not have been suddenly improvised, and must therefore have been prepared in advance, perhaps at the earlier period, when he was considering the chances of forcing a way into the Gulf. Fire was the new weapon, arrows wreathed with oiled and blazing tow were shot at the towers and bulwarks of the enemy. Rafts laden with combustibles were set on fire, and towed or pushed down upon the drifting sea-castles. Ship after ship burst into flame. As the fire spread some tried vainly to master it; others, at an early stage, abandoned their ships, or surrendered. As the resistance of the defeated armada gradually slackened, and about four o'clock came to an end, it was found that a number of ships had taken refuge in the narrows and the Gulf; others were aground on the point; a few had been sunk, some more had surrendered, but numbers were drifting on the sea, wrapped in smoke and flame. Some of these sank as the fire reached the water's edge, and the waves lapped into the hollow hull, or the weight of half-consumed upper works capsized them. Others drifted ashore in the shallows, and reddened sea and land with the glare of their destruction far into the night.
For the men who had fought, the victory, complete as it was, had an element of disappointment. They had hoped to secure as a prize the treasures of Cleopatra, but these had been spirited away on the Egyptian fleet. But for the commanders, Octavian and his able lieutenant, there was nothing to regret. The battle had once more decided the issue between East and West, and had given Octavian such advantages that it would be his own fault if he were not soon master of the Roman World.
Within a few days the remnant of the defeated fleet had been surrendered or burned at its anchors. The army of Canidius, after a half-hearted attempt at an inland march, and after being further weakened by desertions, declared for Octavian, and joined his standards.
Cleopatra had entered the port of Alexandria with a pretence of returning in triumph from a naval victory. Laurel wreaths hung on spars and bulwarks, flags flew, trumpets sounded, and she received the enthusiastic greetings of Greeks and Egyptians as she landed. But the truth could not be long concealed, and under the blight of defeat, linked with stories of leaders deserting comrades and allies, Antony and Cleopatra failed to rally any determined support to their side when the conqueror of Actium came to threaten Egypt itself. Both ended their lives with their own hands, Cleopatra only resorting to this act of desperation when, after breaking with Antony, she failed to enslave Octavian with her charms, and foresaw that she would appear among the prisoners at his coming triumph in Rome.
2 September, B.C. 31—the day of Actium—is the date which most historians select to mark the end of the Roman Republic and the beginning of the Empire. The victor Octavian had already taken the name of his grand-uncle, Cæsar. He now adopted the title of Augustus, and accepted from army and senate the permanent rank of Imperator, inaugurating a system of absolutism that kept some of the forms of the old Republic as a thin disguise for the change to Imperialism.