Mercenary Armies are described as soldiers who are paid by a foreign country to fight in its army. History is filled with these fighting forces made up of freelance warriors who never pledged their allegiance to any particular nation or king.
The troops were a force to be reckoned with, here are six of history's most infamous and influential private armies, according to History:
1. The Ten Thousand
According to Xenophon's "Anabasis," the "Ten Thousand" were a group of Greek warriors contracted by Cyrus the Younger to help oust his brother King Artaxerxes II from the Persian throne.
The Hellenic soldiers-for-hire, many of them hardened veterans of the Peloponnesian War, fought alongside Cyrus and his rebel army in a clash with the King's forces near Baghdad IN 401 BC.
However, Cyrus was killed in the battle and even though the 10,000 held their own in combat, the mercenaries' generals were double-crossed and murdered while trying to negotiate a retreat, says History.
After electing Xenophon as one of their new leaders, The surviving members of the Ten Thousand were forced to band together and fight their way out of enemy territory. The grueling nine-month odyssey landed them all the way at the Greek Black Sea port at Trapezus.
"Despite facing constant ambushes, punishing weather and famine, they arrived on friendly soil with nearly three-fourths of their numbers still intact. Xenophon's account of the Ten Thousand's fighting retreat has since become a classic tale of heroism, and even served as the inspiration for the 1979 cult film "The Warriors," reports History.
2. The White Company
In 14th-century Italy, the White Company had become one of the most infamous of the so-called "free companies"—bands of for-profit soldiers who conducted the lion's share of warfare.
The unit became prominent in the 1360s before falling under the command of Sir John Hawkwood, an Englishman who had been knighted for his service in the Hundred Years' War.
With the help of Hawkwood's leadership, the White Company became known as one of the most elite mercenary armies in Italy.
According to reports, its troops, made up of English, German, Breton and Hungarian adventurers, were renowned for their skill with the longbow and the lance, and they terrified opponents with their lighting-quick surprise attacks and willingness to do battle during harsh weather or even at night.
The men of the White Company made a killing by auctioning their services off to the highest bidder.
Between 1363 and 1388, they fought both for and against the Pope, the city of Milan and the city of Florence, but they were rarely out of the field even during times of peace. In fact, when unemployed, the adventurers often kept their coffers full by launching raids on nearby villages and towns.
3. The Swiss Guard
Although today the Swiss Guard is known as striped-uniformed protectors of the Pope in the Vatican, in history, they were bands of mercenaries that flourished during the Renaissance. Between the 15th and 19th century, more than one million Swiss adventurers fought in Europe's armies, mostly for the French.
They were among the first troops to master the use of pikes and halberds against more heavily armored foes, and by the 1400s, their revolutionary tactics and sheer ruthlessness had earned them a reputation as the best contract troops money could buy.
In 1506, A small contingent of 150 Swiss soldiers of fortune began serving as papal bodyguards and become the official watchmen of the Vatican despite the mercenaries ban in Switzerland. Nearly four-fifths of the Swiss Guard were slain while defending Pope Clement VII from capture during an attack on Rome in 1527.
Today, Swiss Guards are required to be Roman Catholics, stand at least 5 foot 6 inches tall, and have a military background. Even though their roles have been watered down to ceremonial ones, in the past they have been required to fight to protect the pontiff.
4. The Flying Tigers
First organised in 1941, months before the bombing of the Pearl Harbour, the American Volunteer Group, the famed "Flying Tigers" were a three-squadron force of fighter pilots who fought with the Chinese against the Japanese during World War II.
President Franklin D Roosevelt allowed former US military officer Claire Chennault to quietly recruit fighter jocks from the ranks of the US Army Air Force to prevent the Japanese takeover of China while still remaining neutral.
Chennault's mercenaries earned between $600 and $750, along with a $500 bonus for each Japanese aircraft they shot down while regular Air Force pilots received a salary of around $260 a month.
According to the occifial History website, the records reveal that the "Flying Tigers"—famous for the iconic rows of shark teeth painted on the noses of their P-40 fighters—went on to rack up an unprecedented combat record. Despite flying slower, less maneuverable fighters than the enemy, the Americans downed 296 Japanese aircraft and destroyed more than 1,300 riverboats, all while only losing 69 planes and some two-dozen men.
In July 1942, the group officially disbanded, leaving some members to rejoin their old units and served for the remainder of World War II.
5. The Catalan Grand Company
Organised in 1302 by Roger de Flor, the Catalan Grand Company was primarily composed of rugged Spanish veterans of the War of the Sicilian Vespers in Italy. After the war, De Flor and his 6,500mercenaries contracted themselves to the Byzantine Emperor Andronicus II, and helped sweep the Ottoman Turks away from Constantinople
The ones that survived the second conflict embarked on one of the bloodiest and most bewildering adventures in medieval military history.
According to History's article, following an abortive attempt to establish an outlaw state in Gallipoli, they marched to Greece and found work as muscle for the Duke of Athens. But when a dispute arose over back pay, the Catalans once again went to war with a former employer. After crushing the Greek armies and killing the Duke at 1311's Battle of Kephissos, they found themselves the de facto lords of the Duchy of Athens. Amazingly, the mercenaries managed to consolidate their power and rule over large swaths of Greece for more than 75 years until an army from Florence finally defeated them in battle. The remnants of the Catalan Grand Company disbanded shortly thereafter.
6. The Varangian Guard
The unit, a band of Viking mercenaries paid to serve as the personal bodyguard of the Byzantine Emperor, first took up their post in the late 10th century for Emperor Basil II. The unit immediately proved useful in putting down a rebellion, and they went on to serve as the protectors of Constantinople for over two hundred years.
Initially, the Varangian Guard was almost entirely composed of hard-fighting, hard-drinking Vikings. However, by the late 11th century, their ranks began to be filled out by Englishmen, Normans and Danes although winning entrance into the unit was no easy task.
The candiates had to demonstrate their prowess in battle and were forced to pay a small fortune in gold as an entrance fee.
Still, the gifts showered on the Varangians ensured that its members left extremely wealthy, and some even went on to achieve positions of immense power. One of the most famous guardsmen was Harald Hardrada, who later claimed the throne of Norway, says History.