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'Six Secret Teachings' -

In the 'Six Secret Teachings,' a paper on civil and military strategy attributed to the 11th-century Chinese general Jiang Ziya, reference is made to specialized elite units trained to operate in remote and inhospitable terrain. Some military historians identify these descriptions as among the first to reveal the existence of a special force of combatants.

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The ninja -

Ninjas emerged in 15th-century Japan as covert agents trained in reconnaissance, espionage, infiltration, deception, ambush, and bodyguarding. Each was deadly efficient in martial arts.

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Napoleonic Wars -

The Napoleonic Wars saw the establishment of rifle and sapper units handed specialized roles in reconnaissance and skirmishing. They operated outside the normal chain of command and away from formal battle lines. Napoleon's Voltigeur units, for example, were a hand-picked company of irregular riflemen in each regiment of the French infantry tasked with forming skirmish lines and screening the battalion from the enemy.

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Corps of Guides -

The Corps of Guides was a regiment of the British Indian Army that operated across the North West Frontier throughout the latter half of the 19th century during the border wars. Comprised of British officers and Indian enlisted soldiers, the corps was an elite unit known for its bravery and efficiency in dispatching the enemy.

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5th Gurkha Rifles (Frontier Force) -

The 5th Gurkha Rifles (Frontier Force) were formed in 1858. An infantry regiment of the Indian Army comprising Gurkha soldiers of Nepalese origin, the Frontier Force comprised a detached unit, the Gurkha Scouts—one of the first specialized army units to fight independently of central command.

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American Civil War -

While no special forces operated on either side during the American Civil War, irregular warfare was commonplace, anything from surprise raids to bushwhacking carried out by guerilla units and partisan rangers.

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Boer War scouting units -

During the Second Boer War (1899–1902), the British Army drew on the expertise of enlisted men who were well versed in the arts of marksmanship, field craft, and military tactics. These experienced individuals were recruited into scouting and sniper units and deployed behind enemy lines to considerable effect.

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The Luna Sharpshooters -

The specialized professional guerilla unit known as the Luna Sharpshooters was named after Filipino army general Antonio Luna, who fought in the Philippine–American War (1899–1902). A team of marksmen feared for their devastating accuracy on the trigger, the sharpshooters spearheaded every major battle in the conflict.

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Stormtroopers -

The First World War witnessed the formation of the first modern shock troops—stormtroopers. Specialist soldiers of the German Army, stormtrooper units were created out of the need to break out of the impasse of trench warfare. Highly trained and ruthlessly efficient, these units were autonomous in their decision making and used blanket fire cover to move forward across no man's land and breach Allied lines at predefined points. Stormtroopers would again prove their worth in the Second World War.

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The Arditi -

Arditi, which translates to English as "The Daring [Ones]," was the nickname given to Italy's special forces during the First World War. Assigned the tactical role as shock troops, the reparti d'assalto (assault units), to give them their official name, garnered a reputation as one of the most feared corps on the battlefield.

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The Commandos -

Modern special forces emerged shortly after the outbreak of the Second World War with the formation of British Commando units, established at the behest of Winston Churchill. The commandos evolved out of the Special Service Brigade, formed earlier from army recruits. Only the toughest and bravest, however, progressed to a commando unit.

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The Special Air Service -

It was in 1941 that the world's most celebrated and respected special forces unit was formed—the Special Air Service (SAS). Born from an unorthodox idea and plan by Lieutenant David Stirling, the SAS worked in small teams of highly trained soldiers and used the elements of stealth and surprise to carry out raids in the Western Desert, often deep behind enemy lines.

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The Special Boat Service -

Formed a year earlier in 1940 but often referred to as the SAS's sister unit, the Special Boat Service (SBS)—also known as the Special Boat Section—is the special forces unit of the United Kingdom's Royal Navy. Deployed throughout the Second World War as a sea-borne assault unit, its members were drawn from commando regiments and were highly trained in maritime warfare.

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Commandos Marine -

The Commandos Marine, the Special Operation Forces (SOF) of the French Navy, was formed in 1942 from Free French volunteers from different services, and modeled on the British Commandos. It took part in the Normandy Landing on D-Day under the command of Lieutenant Commander Philippe Kieffer, on Sword Beach.

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The Chindits -

Meanwhile in the South-East Asian theater, the Chindits were formed. These were special operations units of the British and Indian armies whose specialist military tactics included long-range penetration and reconnaissance, attacking Japanese troops, and sabotage.

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Bradenburgers -

Formed and operated by the German military's intelligence branch the Abwehr, the Bradenburgers were members of the Brandenburg German special forces unit during the Second World War. Later, the 502nd SS Jäger Battalion, headed by Otto Skorzeny (pictured), a special forces unit formed in 1943, would take part in the rescue of deposed Italian dictator Benito Mussolini in what became known as Operation Eiche.

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Cichociemni -

The Cichociemni, or the "Silent Unseen," were elite special-operations paratroopers of the Polish Army in exile. Trained by Polish and British Special Operations Executive (SOE) operatives, the Cichociemni saw limited action in German-occupied territory due to their small numbers. Ninety-one operatives took part in the doomed Warsaw Uprising of 1944.

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Special Z and M Units -

Australian special forces, notably Z Special Unit and M Special Unit, saw action against the Japanese in the South West Pacific Area and in Timor and New Guinea. Later, in 1957, the Special Air Service Regiment (SASR), Australia's top-tier special forces unit, was created.

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Office of Strategic Services -

In 1942, the Office of Strategic Services (OSS) was founded in the United States. Headed by William J. Donovan, the OSS was responsible for organizing numerous intelligence gathering operations in Nazi-occupied Europe and later in the South-East Asian theater. The OSS was the predecessor of the Central Intelligence Agency (CIA).

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Marine Raiders -

To help combat Japanese forces in the Pacific, the US Marine Corp activated a battalion of troops that became known as the Marine Raiders. Tasked with securing beach heads and other strategic targets, the Marine Raiders were the first special operations force of the United States.

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United States Army Rangers -

United States Army "ranger" units have been in existence since the 17th century. The 75th Ranger Regiment, however, traces its lineage to three of six battalions raised in the Second World War. It remains the premier light infantry unit and special operations force within the United States Army Special Operations Command.

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Merrill's Marauders -

Named after General Frank Merrill and officially called the 5307th Composite Unit (Provisional), Merrill's Marauders was a long-range penetration special operations jungle warfare unit, which fought in the South-East Asian theater during the Second World War.

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First Special Service Force -

Formed in 1942, the 1st Special Service Force was an elite American–Canadian commando unit operating under the command of the US Fifth Army. Its fearsome reputation was such that the 1st became known as the "Black Devil's" or the "Devil's Brigade." The modern American and Canadian special operations forces trace their heritage to this unit.

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Alamo Scouts -

The reconnaissance unit of the Sixth United States Army in the Pacific theater during the Second World War was called the Alamo Scouts. The unit became famous for liberating American prisoners of war (POWs) from the Japanese Cabanatuan POW camp near Cabanatuan, Nueva Ecija in the Philippines in January 1945.

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Donkey Squads -

The so-called "Donkey Squads" were units of partisan forces comprised of anti-communist North Korean defectors who engaged in guerrilla warfare. Formed under the United Nations Partisan Infantry Forces, the Donkeys had a huge impact on the United States effort during the conflict. Pictured: United States Marines watch over North Korean prisoners.

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Israel Defense Forces -

Commando Unit 101 is the founding Israeli special forces unit, created in 1953. The commandos operate under the auspice of Sayeret Matkal, reconnaissance units in the Israel Defense Forces (IDF). One of Sayeret's most spectacular successes was Operation Entebbe in 1976.

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United States Navy SEALs -

The United States Navy Sea, Air, and Land (SEAL) Teams, commonly known as Navy SEALs, were formed in 1962, though units have their origins in the Second World War. SEALs were active during the Korean War and later in Vietnam. They remain the US Navy's primary special operations force: it was a SEALs team that shot and killed Osama bin Laden in 2011.

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Delta Force -

In 1977, US Army Special Forces officer Charles Alvin Beckwith created the 1st Special Forces Operational Detachment–Delta (Airborne). Better known as Delta Force, this is the premier counterterrorism and asymmetrical warfare unit of the US Army.

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Special forces today -

Throughout the latter half of the 20th century and into the 21st century, special forces have played an increasingly prominent role in military operations around the world. Elite military units with distinct areas of expertise often better achieve objectives as small anonymous specialists rather than as a larger, more conspicuous fighting component.

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Global operations -

High-profile wartime and peacetime military operations involving special forces include the Falklands War, The Troubles in Northern Ireland, the first and second Gulf Wars, and in Ukraine, where the Security Service of Ukraine (SBU) maintains its own elite special forces unit called Alpha Group. 

Sources: (The British Empire) (The Company of Military Historians) (National Army Museum) (ARSOF History) (Jewish Virtual Library)

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