ANOTHER ALEXANDER: THE "ANABASIS" OF ANTIOCHUS THE GREAT

Everybody knows about the conquest of the Persian Empire by Alexander the Great, but few know of a military expedition that echoed it in many ways, but was also radically different. This is the "Anabasis of Antiochus III the Great, a campaign that took place over a hundred years after the death of Alexander and was conducted by the king of one of the states that sprang up in the wake of the short-lived Macedonian Empire.

Taking territory is often easy; keeping it can be a lot harder. In the case of the vast territories conquered by Alexander it was even harder, and by 212 BC, the biggest successor state, the Seleucid Empire, which once stretched from the Mediterranean to India, was in a state of near collapse and fragmentation. In short, the East had to be re-conquered and Antiochus III, aged 29, was just the man the man to do it.

Anabasis is a Greek term for "journey up" or "expedition inland," and that is exactly what this was, albeit with an army that is estimated at around 18,000–20,000 by the Hellenistic historian John D. Grainger. This army is thought to have been made up of 12,000–13,000 infantry, 4,000–5,000 cavalry, and 1,000–2,000 auxiliaries, such as archers, slingers, and engineers, essential for sieges and support in diverse terrains. Anything bigger would have involved logistical difficulties. 

Setting out from his capital city Antioch, near the Mediterranean coast of Syria, Antiochus first proceeded North-East to Armenia, a Satrapy that had once paid tribute to the Seleucid Empire, but which now considered the Empire too weak to exact its dues. The Armenians and their Satrap Xerxes however proved too weak to prevent the advance of Antiochus's army, and he soon reached their capital city of Armosata, somewhere on the Upper Euphrates River.

As Antiochus prepared to besiege the city, Xerxes fled and then entered into negotiations. Using diplomacy backed by force, Antiochus got Xerxes to recognize his hegemony and pay a token tribute (only 300 talents, 1,000 horses, and 1,000 mules), in return marrying him to his sister Antiochis.

Click map to enlarge

The campaigns of Alexander (red lines) and Antiochus III (purple lines) compared: (1) Antioch, (2) Armosata, (3) Anihata & Ecbatana, (4) Mt Labus & Syrinx, (5) Alexandria Areion, (6) Bactra, (7) Kingdom of Sophagasenus, (8) Persis, (9) Gerrhaeans, (10) Babylon

After these exertions, Antiochus appears to have had a long rest in the area, resuming his Anabasis in 210 BC. This time his target was the Kingdom of Parthia, which had declared outright independence from the Seleucid Empire around 247 BC. This was located in what is now the North Eastern quarter of Iran, and 200 years later would grow into a major empire and rival of the Roman Empire. 

Antiochus's route took him South-East towards Media (the North Western quarter of Iran) and its capital city of Ecbatana. This was still a compliant part of the Empire, as demonstrated by the relative ease with which the king was able to plunder 4000 talents from the major Zoroastrian Temple of Anahita, before he reached Ecbatana. This would be roughly equivalent to $15.04 billion today in terms of purchasing power.

With these enhanced financial resources, he approached his next target Parthia in 209 BC. the Parthian king Arsaces II deployed scorched-earth and hit-and-run tactics in an effort to impose logistical pain on the Seleucids. This included destroying wells in the parched landscape, but Antiochus countered by deploying 1,000 light cavalry under a general called Nicomedes to secure vital sources of water before they could be tampered with. This allowed him to advance on the Parthian heartland, and thus force the Parthians to stand and fight in the first real battle of the campaign at a place called Mount Labus.

Seleucid phalanx

Grainger's estimate is that Antiochus had 20,000–22,000 men, including 12,000–14,000 infantry, 6,000–7,000 cavalry, and 2,000–3,000 auxiliaries such as archers, slingers, and euzones, a specialist kind of light infantry.

Grainger estimates Arsaces's army at approximately 12,000–15,000, consisting of 9,000–10,000 cavalry (horse archers and cataphract heavy cavalry) and 3,000–5,000 light infantry. Antiochus defeated both their infantry (easy) and cavalry (more difficult), using the euzones to outflank them.  

Following his victory, Antiochus did not proceed to the Parthian capital of Hecatompylus, located about 50 miles from the South East corner of the Caspian Sea. Instead, he advanced on the city of Syrinx, inhabited by Greek settlers. The Parthians, however, determined to defend it, forcing a full siege. In order to capture it, Antiochus's army had to fill in three trenches (40 feet wide and 20 feet deep) before they could attack and breach the walls. The Parthians then escaped and fled, having first butchered the Greek inhabitants (possibly up to 5,000 people). 

"The Great King of the Parthians Hunts with his Tame Panthers" by Jan van der Straet

This hard-won siege, combined with Antiochus's reputation for leniency, was enough to encourage Arsaces II to sue for peace and acknowledge Seleucid suzerainty.

However, Antiochus was reluctant to put the new "friendship" to the test by remaining in Parthia too long, and instead pushed on in the same year to attack the kingdom of Bactria, located mainly in what is now Afghanistan.

Around 250 BC, the Bactrian satrapy had declared itself independent of the Seleucid Empire, and was now ruled by its Greek king Euthydemus I, who had seized power in 225 BC. Euthydemus defended his kingdom with an army, consisting mainly of 10,000 cavalry, at the Arius River (now the Hari Rud River), resulting in the second and last major battle of the campaign. Antiochus won the battle by leading a daring cavalry charge across the river at night, suffering a blow in the face in the process.

The defeat of Euthydemus's army allowed Antiochus to place the Bactrian capital of Bactra under siege in 208 BC. This siege was protracted due to the strong walls, the high morale of the defenders, the counter-siege operations of Euthydemus, and the logistical difficulties of Antiochus. After two years of siege warfare, diplomacy was used to break the deadlock, with Antiochus and Euthydemus entering into an alliance that was cemented by the marriage of Euthydemus's son to Antiochus's daughter Laodice.  Euthydemus kept his title of king but paid tribute, and even supplied war elephants to Antiochus. 

With Bactra onside, it was now possible for Antiochus to follow Alexander's route down the Khyber Pass to India and the prospect of even more elephants. His visit to India seems to have been largely peaceful, as there are no records of battles.

The once powerful Mauryan Empire had by this time declined and was fragmenting. In the area of the Khyber pass, Antiochus met the Indian king Sophagasenus, who appears to have paid a token tribute, including more elephants, bringing Antiochus's total up to 150. There may have been some joint operations between the two into the area of the Punjab, but the surviving accounts are silent on this. Suffice to say, his penetration of the Sub-Continent was a lot less noticeable or recorded than that of the Alexander the Great, or that of the Greco-Bactrians, who invaded and conquered much of Northern India around twenty years later.

From India, Antiochus's route took him back into modern-day Afghanistan (via modern-day Kandahar), then through South Eastern Iran to Persis, which he reached in 205 BC. This was the original homeland of the Persians and an area he had already visited in a previous campaign when it rebelled in 222 BC. 

The total insanity of elephant warfare

In 204 BC, he advanced into the Persian Gulf, campaigning against the city of Gerrha (in modern-day Saudi Arabia). This seems to have been a sea and land operation, and was probably motivated by asserting control over trade routes that ran to India. After some resistance, the Gerrhaeans appear to have bent the knee and paid the usual tribute. This is also significant as the only part of the Anabasis that took place on territory that had not been formerly visited by Alexander on his route of conquest. 

The expedition also prefigured Antiochus's later career. In his subsequent defeat against the Romans at the Battle of Magnesia in 190 BC, his army included not only war elephants but also 6000 Parthian cataphracts and 1,200 Dahae archers from the lands to the North of Bactria.

Also, his successful plunder of 4,000 talents from the Temple of Anahita prompted him to later attack another rich temple, but this time with much less success. Three years after Magnesia, which had proved very costly, he attempted to plunder the  Temple of Bel in Elymaïs (southwestern Iran) in order to restock his coffers. This led to fighting, in which he was killed at the age of 55.

With the occasional minor revival, the Empire then slowly declined until it was finally extinguished in 64 BC, when the Roman general Pompey incorporated the remaining Seleucid territories into the Roman province of Syria.