The Persian War Machine: The Immortals – Part II


The Persian war machine made empires beforehand look miniature. The Persians were able to take the best from all over the Near East and turn it into a force that could not be defeated for many centuries to come.

[Read Part I here]

Many Guard Units

Herodotus states in 7.40 that “For before him (King) went first a thousand horsemen, chosen out of all the Persians; and after them a thousand spearmen chosen also from all the Persians, having the points of their spears turned down to the ground; and then ten sacred horses, called “Nesaian,” with the fairest possible trappings.” The thousand spearmen marched with their spears reversed, and the spear butts, which would normally have a point, were replaced with “golden pomegranates.” Herodotus refers to these men as “spear-bearers.” These men were the king’s own spear-bearers.

Furthermore, Herodotus 7.41 mentions that once the thousand horsemen passed by, they were followed by ten thousand men who “went on foot; and of these a thousand had upon their spears pomegranates of gold instead of the spikes at the butt-end, and these enclosed the others round, while the remaining nine thousand were within these and had silver pomegranates. And those also had golden pomegranates who had their spear-points turned towards the earth, while those who followed next after Xerxes had golden apples.” While the passage provided describes what appears to the famous “immortal” it appears not. A thousand had upon their spears butts ‘pomegranates of gold’, while the remaining nine thousand had ‘silver pomegranates’. Behind the ten thousand came another thousand had ‘golden apples.’ While it appears that this is not the ten thousand as some suggest, perhaps it is. In other words, the thousand spearmen who’s spear-butts had a golden pomegranate were perhaps the captains in charge of the nine thousand. But who were the “Immortals”?

The Immortals

Herodotus makes the first mention of them in Histories 7.83 stating, “these ten thousand chosen Persians the general was Hydarnes the son of Hydarnes; and these Persians were called “Immortals,” because, if any one of them made the number incomplete, being overcome either by death or disease, another man was chosen to his place, and they were never either more or fewer than ten thousand.” While Herodotus calls them by this title, they are not mentioned during the reign of Xerxes. Xenophon, who came later, does mention that Cyrus established a personal guard of ten thousand spearmen and mentioned they the guard of ten thousand was still existent when he wrote this in the 360s BCE.

Modern reenactors of the Immortals in their ceremonial dress at the 2,500-year celebration of the Persian Empire.

Modern reenactors of the Immortals in their ceremonial dress at the 2,500-year celebration of the Persian Empire. (Public Domain)

The Immortals were a fearsome army of ten thousand men that was created by Cyrus the Great to guard him, and were recruited from the lower classes of Persia to serve as the king’s personal bodyguard day and night, and wherever the king went so did they. The name Immortals comes from that whenever one of them got ill, wounded, or even died, he was replaced quickly with another man to ensure that the number stayed at ten thousand.

The Immortals were more than just mere spear-bearing infantry. In times of war, the Immortals surrounded the king while the inner core of Immortals consisted of two royal regiments; The first being infantry that carried a composite bow with a seven-foot-long spear and an akinakes (a dagger or short sword).

The second royal regiment of the Immortals was cavalry archers who carried spears and the majority of the Immortals that surrounded them were infantry. To give you a better picture of the Immortals in terms of battle formation. The front rank consisted of infantry carrying shield and spear, the spear they carried was seven feet in length, and they were the front, rear, and sides of the formation. They provide protection for the archers behind them while the cavalry likely stayed outside of the formation protecting the flanks.

Mosaic depicting Persian archers. (Pre 4th Century BC)

Mosaic depicting Persian archers. (Pre 4th Century BC) (CC BY 2.0)

Besides the Immortals, there was the cavalry. The cavalry only made up 10 percent of Cyrus’s army in the early days of his conquest while the other 90 percent of the army was infantry, or should we say foot soldiers. As time went on, Cyrus noticed the importance and the effectiveness of cavalry forces. He thus added more cavalry to his army and reduced the amount of foot soldiers to get a better ratio that was 20 percent cavalry and 80 percent infantry. The cavalry would have been mostly light and carrying only a bow, and were mainly of non-Persian ethnicity but were commanded for the most part by Persian officers. Their duty was to harass the enemy with a barrage of arrows and draw them into an attack, a hit-and-run you could say that would be annoying to any attacker.

Persian nobles formed the heavy cavalry. They were armed with two javelins, a lance made of wood and sometimes metal, and they carried an akinakes as well as a small oval shield. The armor of a heavy cavalryman was made of leather overlapped with metal disks or scales of bronze, iron, or gold, and was often colored in order to distinguish one unit from another. This must have been an impressive sight on a sunny day—unless you were the enemy.

Persian infantry varied between light and heavy. The light units carried spear and swords while their heavier counter parts carried a longer spear a shorter sword and a battle-axe. These heavier infantries wore black hoods that covered their head and much of their face. In combat, the front rank of the phalanx carried a shield made of wicker and a single spear while the ranks behind them carried no shield but had two spears on hand. Their main function was to toss the first spear over the front rank while keeping the other spear on hand for close combat. The heavier infantry, the elites, otherwise known as the Immortals, were the ones who kept silent when marching en masse. It must have been eerie for those about to receive the sword on the other end of the battlefield, when all you felt was the earth tremble slightly under your feet while an army of silence approached you from the other end. It was common for most warriors to scream and shout when in combat in order to intimidate their opponent. The immortals did the exact opposite. They killed in silence.


Besides the cavalry and infantry units of the Persians, there were the charioteer units. The Persian chariot was slightly higher and heaver then their Assyrian, Egyptian and Babylonian counterparts. Its wheels and axle were heavier and the platform on which the soldiers stood was much wider and carried two men. One man was to drive the heavy, cumbersome vehicle, and the passenger was a soldier, either a spearman or an archer. It took four horses to pull this chariot, which is a considerable amount of power compared to chariots pulled by two horses. To make it even more deadly, Cyrus had scythes installed on the axles, which extended two yards out from the wheel. Overall, it was a deadly machine when the opportunity presented itself on the battlefield since no charioteer, or for that matter horse, would plow into a forest of spear points and shields. It was more effective against light infantry, loose formations, and troops of undisciplined men unwilling to stand their ground in the face of combat.

Persian scythed chariots.

Persian scythed chariots. (Public Domain)

Cyrus also introduced the use of siege weapons into his ranks. Siege towers weighing in at seven tons when fully staffed and were twenty-four feet (7.3 meters) high had to be pulled by sixteen oxen. It is said that each story of the siege tower was about three stories in height, and was manned by twenty archers, giving it a total of 60 archers inside. These siege towers were also used as a command center for the Persian army and were great for surveillance due to its height.

An English siege tower, representational image.

An English siege tower, representational image. (Public Domain)

The Persians also had a special unit that used naphtha during sieges. Naphtha is similar to “Greek fire” a chemical mixture of a thinner consistency than oil. The purpose of naphtha was to burn wooden structures in combat. The Persians would use this during siege warfare by shooting flaming arrows over the enemy’s walls hoping to hit the wooden rooftops in the city thus causing a blaze that could spread throughout. Alternatively, they used it for defensive purposes by burning wooden siege equipment the enemy brought forth to the walls. In addition, the combat engineers of the Persian army were of great importance to the army. For they would move ahead of the army to repair or build roads and bridges, to dig ditches, and used pontoon boats as floats for bridges to get their massive and heavy army across.

To move this huge army was a feat in itself. The Persians, with all the ingenuity and complexity of their military system, had to have a supply line able to provide this juggernaut when on the move. The job of supplying the army was left to the commissariat. When the army was on the move, the commissariat was split into two, with one in front of the army and another in the rear. The commissariat who moved ahead of the army was tasked to look for suitable places to encamp where clean water could be found and the livestock could be grazed for a brief time before they moving on. The rear commissariat was tasked to keep the army supplied with all types of weaponry such as bows, swords, spears, arrows, armor and many other items that would be needed. Now, due to the amount of equipment the commissariat provided they would eventually run low, and in order to solve this problem the Persian king required that each satrap (governor) keep a certain amount on hand for the incoming army when it arrived to restock before the next big move.

While this small piece on the Persian military only skims the surface, understand that what Cyrus created came about with the aid of his many allies and most importantly, the trial and error of battle. Cyrus, once in power, began to formulate an army capable of adopting what was practical and functional when it came to the art of command and control on the battlefield. After his death, the Persian military maintained this, making few adjustments.

Immortals fighting Alexander's troops. Color reconstruction of the original reliefs on the Alexander Sarcophagus, in Istanbul.

Immortals fighting Alexander’s troops. Color reconstruction of the original reliefs on the Alexander Sarcophagus, in Istanbul. (CC BY-SA 3.0)

Overall, the Persian army was a professional fighting force of a complex magnitude that in many ways would not be matched until the Macedonian and Roman Empires. However, with their professionalism, also came their weakness. As stated before, they were complex. The Persians, even though they could field a huge army that was disciplined, they were homogenous nor were all of them skilled in the same weapons. Persia had its own standing army that was professional but too small, while the many regions under Persian control provided a hodgepodge of military units all accustomed to their own fighting style and practice. Many of these units were light infantry such as archers and spearmen with little to no armor what so ever. The Persians relied on quantity over quality in its military ranks. It worked well for the region of the world they were in, but as time went on, they faced armies who were all about amour and standard structure, and who may have been small in comparison but undoubtedly more disciplined.

Cam Rea is an author and military historian. He has written numerous articles for Ancient Origins Premium and Classical Wisdom Weekly as well as several books.

Top Image:  Deriv; Faravahar carved in stone at Persepolis, Iran, (Public Domain) and Achaemenid soldiers.

By Cam Rea


Briant, Pierre. ‘From Cyrus to Alexander: A History of the Persian Empire’. Publisher: Eisenbrauns; 1st English Edition edition (January 1, 2002)
Farrokh, Kaveh. ‘Shadows in the Desert: Ancient Persia at War’. Publisher: Osprey Publishing (2007)
Head, Duncan. ‘The Achaemenid Persian Army’. Publisher: Montvert (1992)
Herodotus, Histories
Strabo, The geography of Strabo.
Xenophon, Cyropaedia

Leave a Reply