Antony initially planned to anticipate an attack by descent upon Italy toward the end of 32 BC; he went as far as
Corcyra. Finding the sea guarded by a squadron of Octavian's ships, Antony retired to winter at
Patrae while his fleet for the most part lay in the
Ambracian Gulf, and his land forces encamped near the promontory of Actium, while the opposite side of the narrow strait into the Ambracian Gulf was protected by a tower and troops. After Octavian's proposals for a conference with Antony were scornfully rejected, both sides prepared for the struggle the next year. The early months passed without any notable events, other than some successful forays by Agrippa along the coasts of Greece, primarily designed to divert Antony's attention. In August, troops landed near Antony's camp on the north side of the strait. Still, Antony could not be tempted out. It took some months for his full strength to arrive from the various places in which his allies or his ships had wintered. During these months Agrippa continued his attacks upon Greek towns along the coast, while Octavian's forces engaged in various successful cavalry skirmishes, so that Antony abandoned the strait's north side between the Ambracian Gulf and the Ionian Sea and confined his soldiers to the southern camp. Cleopatra now advised that garrisons be put into strong towns and that the main fleet return to Alexandria. The large contingent furnished by Egypt gave her advice as much weight as her personal influence over Antony, and it appears that this movement was agreed to. Octavian learned of this and debated how to prevent it. At first of a mind to let Antony sail and then attack him, he was prevailed upon by
Agrippa to give battle. On 1 September he addressed his fleet, preparing them for battle. The next day was wet and the sea was rough. When the trumpet signal for the start rang out, Antony's fleet began issuing from the straits and the ships moved into line and remained quiet. Octavian, after a short hesitation, ordered his vessels to steer to the right and pass the enemy's ships. For fear of being surrounded, Antony was forced to give the word to attack.
Order of battle The two fleets met outside the
Gulf of Actium on the morning of 2 September. Antony's fleet had 250 larger
galleys, with towers full of armed men. He led them through the straits towards the open sea. Octavian's fleet had 400
galleys. His fleet was waiting beyond the straits, led by the experienced admiral Agrippa, commanding from the left wing of the fleet,
Lucius Arruntius the centre, and
Marcus Lurius the right.
Titus Statilius Taurus Antony's personal flagship, like his admirals', was a "ten". An "eight" war galley had around 200 heavy marines, archers, and at least six ballista catapults. Larger than Octavian's ships, Antony's war galleys were very difficult to board in close combat and his troops were able to rain missiles onto smaller and lower ships. The
harpax, Agrippa's device made for grappling and boarding enemy ships, made this task a bit easier. The galleys' bows were armoured with
bronze plates and square-cut timbers, making a successful ramming attack with similar equipment difficult. The only way to disable such a ship was to smash its oars, rendering it immobile and isolated from the rest of its fleet. Antony's ships' main weakness was their lack of manoeuvrability; such a ship, once isolated from its fleet, could be swamped with boarding attacks. Also, many of his ships were undermanned with rowing crews; there had been a severe malaria outbreak while they were waiting for Octavian's fleet to arrive. e on a Roman Galley Octavian's fleet was largely made up of smaller "
Liburnian" vessels. His ships, though smaller, were still manageable in the heavy surf and could outmanoeuvre Antony's ships, get in close, attack the above-deck crew with arrows and ballista-launched stones, and retreat. Moreover, his crews were better trained, professional, well-fed, and rested. A medium ballista could penetrate the sides of most warships at close range and had an effective range of around 200 yards. Most ballistas were aimed at the marines on the ships' fighting decks. Before the battle, one of Antony's generals,
Quintus Dellius, defected to Octavian, bringing with him Antony's battle plans. Shortly after midday, Antony was forced to extend his line from the protection of the shore and finally engage the enemy. Seeing this, Octavian's fleet put to sea. Antony had hoped to use his biggest ships to drive back Agrippa's wing on the north end of his line, but Octavian's entire fleet, aware of this strategy, stayed out of range. By about noon the fleets were in formation but Octavian refused to be drawn out, so Antony was forced to attack. The battle raged all afternoon without a decisive result. Cleopatra's fleet, in the rear, retreated to the open sea without engaging. A breeze sprang up in the right direction and the Egyptian ships were soon out of sight. Lange argues that Antony would have had victory within reach were it not for Cleopatra's retreat. Antony had not observed the signal, and believing that it was mere panic and all was lost, followed the fleeing squadron. The contagion spread fast; everywhere sails unfurled and towers and other heavy fighting gear went by the board. Some fought on, and only long after nightfall, when many a ship was blazing from the firebrands thrown upon them, was the work done. Making the best of the situation, Antony burned the ships he could no longer man while clustering the remainder tightly together. With many oarsmen dead or unfit to serve, the powerful, head-on ramming tactic for which the Octaries had been designed was now impossible. Antony transferred to a smaller vessel with his flag and managed to escape, taking a few ships with him as an escort to help break through Octavian's lines. Those left behind were captured or sunk. J. M. Carter gives a differing account of the battle. He postulates that Antony knew he was surrounded and had nowhere to run. To turn this to his advantage, he gathered his ships around him in a quasi-horseshoe formation, staying close to the shore for safety. Then, should Octavian's ships approach his, the sea would push them into the shore. Antony foresaw that he would not be able to defeat Octavian's forces, so he and Cleopatra stayed in the rear of the formation. Eventually Antony sent the ships on the northern part of the formation to attack. He had them move out to the north, spreading out Octavian's ships, which until this point were tightly arranged. He sent Sosius to spread the remaining ships to the south. This left a hole in the middle of Octavian's formation. Antony seized the opportunity and, with Cleopatra on her ship and him on a different ship, sped through the gap and escaped, abandoning his entire force. With the end of the battle, Octavian exerted himself to save the crews of the burning vessels and spent the whole night on board. The next day, because much of the land army had not escaped to their own lands, had not submitted, or were followed in their retreat to Macedonia and forced to surrender, Antony's camp was occupied, bringing an end to the war.
Alternative theories Scientists researching the "
dead water" phenomenon are investigating whether the Egyptian fleet may have been trapped in dead water, which can substantially reduce the speed of a ship. ==Aftermath==