THE ROMAN LEGION 

    When we say "LEGION" we imagine a group of people in huge scale but what is the Roman Legion? Who were they? How did they conquer the ancient world? How did they appear victorious over so much and impossible odds? Well let's take a look on the ROMAN EMPIRE.

      

    The Roman Empire stretches from northern England in Hadrian's wall to southern part of Egypt and from Iberia (modern day Spain & Portugal) to Babylon (Iraq) at it's peak during the reign of Emperor Trajan.Well it was the Roman Legion that fought and conquer those lands for the glory of ROME. In ancient roman army or legion were recruited from citizens.
The early republican legion were composed of four types of infantry, the Velites, Hastati, Principes, and Triarii.

Velites were light infantry and skirmishers who were armed with a number of light javelins, to harass the enemy and also carried short thrusting swords, or gladii for use in melee. They rarely wore armour, as they were the youngest and poorest soldiers in the legion and could not afford much equipment. They did carry small wooden shields for protection though, and wore a headdress made from wolf skin to allow officers to differentiate between them and other heavier legionaries.

Hastati were originally some of the poorest men in the legion, and could afford only modest equipment—light armor and a large shield, in their service as the lighter infantry of the legion. Later, the  Hastati contained the younger men rather than just the poorer, though most men of their age were relatively poor. Their usual position was the first battle line. They fought in a quincunx formation, supported by light troops. 

Principes were men in the prime of their lives who were fairly wealthy, and could afford decent equipment. They were the heavier infantry of the legion who carried large shields and wore good quality armour. They were deployed second in the line next to the hastati.

Triarii (Singular: Triarius) were one of the elements of the early Roman military Manipular legions of the early Roman Republic (509 BC – 107 BC). They were the oldest and among the wealthiest men in the army, and could afford good or even the finest quality equipment. They wore heavy metal armour and carried large shields, their usual position being the third battle line. The Triarii were rarely used in battle because usually the enemy were defeated by the Hastati and Princepes before the Triarii were committed. 

The Velites, Hastati, Principes, Triarii were done away or converted to other unit after the MARIAN REFORM in 107 BC

Armies in the ancient world would lack mobility without cavalry. 

The Roman equestrian order or Equites

were the early roman cavalry of the republic, they  came from a wealthy family and they provide their own equipment and bought their own horse .They were used to drive off enemy skirmishers and cavalry or attack/defend the flanks. The Equites may not be the best horsemen of the day but they can be a force to be reckoned with. 

THE IMPERIAL LEGION

Generals, during the Republican civil wars, had formed their own legions and numbered them as they wished. During this time, there was a high incidence of Gemina(twin) legions, where two legions were consolidated into a single organization (and was later made official and put under a legatus and six duces). At the end of the civil war against Mark Antony, Augustus Caesar was left with around fifty legions, with several double counts . For political and economic reasons, Augustus reduced the number of legions to 28 (which diminished to 25 after the Battle of Teutoburg Forest, in which 3 legions were completely destroyed by the Germanic tribes led by Arminius).

The LEGIONNAIRE(S) in the images above were definitely different from the republican. They wore lorica segmentata( plate armour ) and some wore lorica hamata (chainmail alike ). Every legionary is a professional soldier, they underwent through harsh training; discipline was the base of the army's success.The soldiers were relentless and constantly trained with weapons and forced marches with full load in tight formation. They were equip with Heavy armour, Scutum (Shield), two pairs of javelin or pila and the short stabbing sword the Gladius for quick stab behind the shield. 

You may watch this short video for more info :)
http://www.youtube.com/watch?v=f_fpOUQcAac

THE PRAETORIAN GUARDS

The Praetorian Guard was a force of bodyguards used by Roman Emperors. The title was already used during the Roman Republic for the guards of Roman generals, at least since the rise to prominence of the Scipio family around 275 BC. The Guard was dissolved by Emperor Constantine I in the 4th century. They should not be confused with the imperial Germanic bodyguard that provided close personal protection for the early Roman emperors.

They were recruited from the best legionnaires  and was chosen to guard VIP in the legion. In later years of the Empire they became corrupt and begun interfering in politics, they often murder emperors who were not in favor of them or indecisive nor not a capable ruler.

Every army have its own general, the legion in war time is led by a military tribune.

Roman Generals were usually politician in Rome that seeks glory and riches, just like the Conquestadoris of the 16th centuries, they also used propaganda to bring roman civilization and peace to all who would embrace. Some became client-estate of ROME (under protection) or allied with them.  Civilizing the barbarians while conquering the long standing enemies such as Carthage and the Greeks give way to the birth of an empire started by Gaius Julius Caesar.

Division in the LEGION

The LEGION is divided into maniples and later cohort in the empire. Every legion is consisted of 10 cohorts, the 1st cohort were the most experience men and most prestigious while the 10th is the least. A cohort consisted of approximately 480 men and commanded by one man. It consisted of six centuriae of 80 men, each commanded by a centurion assisted by junior officers. At various times prior to the reforms, a century might have meant a unit of 60, 80 or 100 men. It is almost certain that the most senior centurion of the six would have commanded the entire cohort. There are many types of cohort, some cohorts were Auxiliary units such as archers for long distance and spear-men to counter enemy cavalry. There are also units of allied cavalry such as the germanics, the equites of ROME and some Italian types of horsemen.

During Battle

Romans against Dacians

In battle they were supreme fighters that relies on teamwork and will hold the line.They would maintain their formation that is carefully planed for a certain terrain or foe such as the Barbarians, Greeks and middle-eastern kingdom. When they approach the enemy or when the foe is approaching they shower them with javelins or pila to weaken them before the melee battle commence. CENTURIONS were given permission to act by his own (and will hold responsible if it goes bad) to exploit gap or weakness in the enemy formation, specially if facing the Greek Phalanx Pike-men

As the image above shows a centurion is leading few men into the gap of the phalanx formation caused by a ragged terrain. The Macedonian Phalanx were improvised version of hoplite phalanx like what you saw in the movie 300, it was Philip of Macedonia that organized it and used to full effect by his son, Alexander the Great by conquering the Persian Empire in his war of revenge because he thought that it was the Persians that were responsible for the assassination of his father and must also pay for what they've done in the past. ( Burning of acropolis in Athens  )

The image below is the Carthaginian Sacred Band Phalanx

The phalanx is impossible to beat in front and it seems unstoppable in the time of Alexander. The Romans realized its weakness because they encounter it in the field of battle many times and specially when they were defeated by Pyrrhus of Epirus in southern Italy.
Although the phalanx is very strong in the front it is very weak if attacked in flanks or in rear because it could not be mobilizes quickly. Mobilizing it would take an hours even half a day. The battle of Cynoscephalae is a great example of the LEGION defeating the phalanx, the Macedonians led by Philip V didn't form is men well enough.

Battle of Cynoscephale.

"The Romans led by Flamininus, still unaware of Philip's location, sent out some cavalry and light infantry to reconnoiter, which engaged Philip's troops on the hills. The battle on the hills grew fierce and Flamininus sent 500 cavalry and 2,000 infantry as reinforcements, mostly Aetolians, forcing Philip's men to withdraw further up the hill. Philip now sent more men into the melee, his Macedonian and Thessalian horse, who drove the Romans down the hill, until the Aetolian cavalry stabilized the situation. Philip, though reluctant to send his phalanx into the broken, hilly terrain eventually ordered an assault with 8,000 men when he heard of the Roman retreat. Flamininus positioned his troops on the field as well. He left his right wing in reserve, with his elephants in front, and personally led the left wing against Philip. Meanwhile Philip's phalanx had reached the summit, and after joining with their light troops and cavalry which he placed on his right wing, Philip had his phalanx charge down the hill into the oncoming legionaries. As the Roman left was slowly being driven back, Flamininus took command of his right and ordered an assault there.

Philip's right wing was now on higher ground than the Roman left, and was at first successful against them. However his left wing and center- made up of another 8,000 phalangites- were still disorganized and in marching formation. They hadn't even formed the phalanx when Flamininus sent his elephants charging into them, and they routed. After breaking through, one of the Roman centurion took twenty maniples (a smaller division of the legion) and attacked the Macedonian right wing from behind. The Macedonians were unable to reposition themselves as quickly as the Roman maniples. Now surrounded by both wings of the Roman legion, they suffered heavy"
http://en.wikipedia.org/wiki/Battle_of_Cynoscephalae

Testudo or Tortoise

In the testudo formation, the men would align their shields to form a packed formation covered with shields from all sides except the rear . The first row of men, possibly excluding the men on the flanks, would hold their shields from about the height of their shins to their eyes, so as to cover the formation's front. The shields would be held in such a way that they presented a shield wall to all sides. The men in the back ranks would place their shields over their heads to protect the formation from above, balancing the shields on their helmets, overlapping them. If necessary, the legionaries on the sides and rear of the formation could stand sideways or backwards with shields held as the front rows, so as to protect the formation's sides and rear.

The Testudo is a defensive formation designed to deflect missile arrows and javelins, it is often used during sieges to minimize casualties. Although it offers great defense against missiles, it sacrifices the mobility of the troops and they were very vulnerable if attack. In the battle of Carrhae Marcus Crassus were ambushed by the Parthians, when he saw the enemy horse archers approaching he ordered his men into testudo formation. They may be safe for a while but the Roman Cavalry that were sent to chase the horse archers were lured in to the trap and were slaughtered by Parthian Cataphracts. Now the legion is vulnerable to the charge of the cataphracts and if they will disassemble the testudo rains of arrows will surely be theirs. The legion with no other choice but to stand and fight to the death were annihilated and the richest man in Rome(Marcus Licinius Crassus) were killed in the dessert and his head was put to pike.

Even the Roman Legion the great military machine of the ancient world suffers great defeats because of the recklessness of their tribunes.  The romans  learned from their mistakes and despite the humiliating defeat at Carrhae the Roman Legion record great victories over their enemies in later centuries.

Strength and Honour, Obedience, Discipline and Resilience to overcome the impossible to achieve a glorious victory for ROME.

THE LATE ROMAN ARMY

From around 250 AD a slow decline began in the quality of the roman infantry.From the 4rth century a.d the great tribal migrations of the Germanic tribes began.Revolts and succession struggles,plus the persistent threat of the new Sassanids in the east.Combined to overwhelm the empire's forces.To combat the more frequent raids and advances of their hostile neighbors the legions were changed from slow and heavy to much lighter troops, and cavalry was introduced as a serious concept.Now there was one cavalryman to 3 infantry to the earlier 1 to 40.The legion was trimmed down to meager 1000-1500 men units.

This meant that the new subdivided infantry lost the awesome power that the earlier legions had, meaning that whilst they were more likely to see a battle they were less likely to win it. That legion size was at an all time low was also a factor.Roman horsemen, while fast and more numerous,were actually much too weak to cope with the very cavalry based invasions of the Huns, Goths, Vandals and Sassanids. Another primary reason was the 'barbarisation of the infantry'. Essentially it is argued that the increasing barbarisation of the heavy legions weakened weaponry, training, morale and military effectiveness in the long run.The italians no longer had citizenship privilege and legions recruited from all over the empire.Most barbarians fought under their own leaders in their own style and since were not Italians generally didn't have the same morale of earlier legions.Such practices as permitting the settlement of massive, armed barbarian populations on Roman territory, the watering down of the privilege of citizenship, increasing use of alien contingents, and relaxation or removal of traditionally thorough and severe Roman discipline, organization and control, contributed to the decline of the heavy infantry.

The Comitatenses

The Comitatenses earn their existence to the military reforms of Constantine the Great. He divided the army into two types of troops: the other half of the system were the Limitanei, or frontier troops. Originally, the comitatenses were regarded as an elite force personally associated with the Emperor, but the needs of Imperial defense soon meant that they were detached as regional field armies across the Roman World. Enemies would be allowed to penetrate the "limes" or frontier line while being delayed by the limitanei, and then be destroyed in detail by the comitatenses.

Commanded by, these were well equipped and professional soldiers, even if not quite the equals of Caesar's legions.

The Limitanei

Limitanei were suposedly second class. Over down, however, the limitanei settled down at their posts and became soldier-settlers with families and farms, rather than purely garrison troops.

Altough a militia of sorts and treated as second class by the mobile comitatenses, the limitanei are fairly well equipped and have good chainmail, helmets, spears and large shields when they fight.

Decline and Fall of ROME

      However internal conflicts, centuries of civil wars and corruption in the senate. Ineffective and indecisive emperors and the Praetorian guards that should have protecting them not interfering nor dispose them led to a slowly decay. Too much cultural diversity that resulted in disunity and revolts due to poverty.Despite the Roman Legion's success for over 500 years it could not prevent nor stop the collapse of the greatest empire the western world have ever seen.

many may not agree on what I wrote ..
PROJECT FOR ENGLISH-1 ^_^
-I'm not an expert historian.