Battles & Wars › World War I › Trench warfare
Tank
first used September 15, 1916· Invention or discovery· Weapons, armor & warships
Well documentedSolid records, physical evidence or scientific consensus.
An armored, tracked fighting vehicle, first fielded by Britain, built to cross trenches and barbed wire under machine-gun fire.
See it on the Battles & Wars map →What happened
Britain's navy, backed by Winston Churchill, funded early 'landships'; the code name 'tank' disguised them as water tanks. The Mark I had a crew of eight, crawled at about 6 km/h and carried cannon or machine guns. At Flers-Courcelette on the Somme, September 15, 1916, many of the first tanks broke down, but some led advances. At Cambrai in 1917 and Amiens in 1918, massed tanks broke through. France built the light Renault FT with a rotating turret.
Why it matters
It ended the machine gun's dominance over attacking infantry and became the core of mobile warfare, from Germany's blitzkrieg to today's armored armies.
How we know
Surviving Mark I and Mark IV tanks at the Tank Museum in Bovington, England, design records, army reports and crew memoirs.
Still debated
Credit for the invention was disputed after the war; a 1919 Royal Commission awarded it mainly to William Tritton and Walter Wilson.
Connections (8)
▸Battle of the Somme saw the first use of TankWell documented
The connection
Desperate for a breakthrough, Haig sent the first tanks into action at Flers-Courcelette on September 15, 1916, before they were fully ready. Of about 49 available, many broke down or got stuck, but some helped take the village of Flers. The debut gave away surprise but taught crucial lessons about using tanks.
When and how
Flers-Courcelette on the Somme front, September 15, 1916; British Mark I tanks with British, Canadian and New Zealand infantry.
How we know
Tank crew reports, war diaries and an airman's famous report that 'a tank is walking up the High Street of Flers' document the debut.
Debates and open questions
Whether using a few tanks early wasted the surprise of a later mass attack, as critics including Churchill argued, is still debated.
▸Tank was built to break Trench warfareWell documented
The connection
Trenches, barbed wire and machine guns made frontal attacks suicidal. The tank answered all three: tracks rolled over wire and crossed trenches, armor stopped bullets, and its guns knocked out machine-gun posts. It brought back protected movement across no man's land, the open ground between the trench lines.
When and how
Designed in Britain in 1915–16 by the navy-led Landships Committee, with William Tritton and Walter Wilson at Foster's works in Lincoln; France developed its own.
How we know
Army requirements called for crossing wide trenches and climbing parapets, and the rhomboid shape, with tracks running round the whole hull, was chosen to meet them.
Debates and open questions
Early tanks were slow and unreliable; historians debate whether they truly broke the deadlock or mainly helped artillery and infantry do it.
▸Tank made possible Blitzkrieg (combined-arms maneuver warfare)Well documented
The connection
World War I tanks were slow and unreliable, used mainly to help infantry cross trenches. Between the wars, faster, radio-equipped tanks and thinkers such as Britain's J.F.C. Fuller and Germany's Heinz Guderian pointed to massed armored formations. Germany grouped its tanks into panzer divisions with motorized infantry and artillery, the striking core of blitzkrieg.
When and how
Germany, mid-1930s: the first three panzer divisions formed in 1935, building on British experiments and secret German tank training in the Soviet Union at Kazan.
How we know
German organizational records and Guderian's 1937 book 'Achtung–Panzer!' document the plan, and panzer divisions led every German breakthrough of 1939–41.
Debates and open questions
German tanks were often not superior; in 1940 many French tanks were better armored. Organization, radios and tactics probably mattered more than the machines.
▸Tank spearheaded Hundred Days OffensiveWell documented
The connection
At Amiens on August 8, 1918, over 500 tanks led the assault alongside infantry, artillery and aircraft, helping advance about 11 km on the first day. Later, tanks were fewer, as many broke down or were knocked out, but they kept helping infantry through wire and strongpoints, and German troops feared them.
When and how
Amiens, France, August 8, 1918, with the British Tank Corps, the Australian and Canadian corps and French tanks; then battles through the autumn.
How we know
Tank Corps records and German reports, including Ludendorff's memoirs, name tanks as a key factor in the Amiens breakthrough.
Debates and open questions
Some historians stress that artillery and infantry tactics, not tanks, won the Hundred Days; tank losses were heavy after the first days.
▸Tank was built to crush Barbed wireWell documented
The connection
British designers built the tank to cross trenches, shrug off machine-gun bullets and flatten wire, opening paths for infantry. First used on the Somme in September 1916 in small numbers, tanks proved the idea at Cambrai in November 1917, where hundreds crushed lanes through the wire without the usual long bombardment that warned the enemy.
When and how
Britain's Landships Committee, 1915; Flers-Courcelette, September 15, 1916; Cambrai, November 20, 1917; Ernest Swinton, William Tritton and Walter Wilson.
How we know
Swinton's 1915 memos and early specifications name crushing wire as a goal; after-action reports from Cambrai record the results.
Debates and open questions
By 1918 improved artillery and fuzes also cut wire well; how much tanks rather than guns beat the wire is debated.
▸Schneider of Le Creusot built France's first TankWell documented
The connection
In late 1915 Colonel Jean-Baptiste Estienne urged an armored tracked vehicle to cross trenches. Schneider engineer Eugène Brillié built one on an American Holt tractor chassis, and France ordered 400 in February 1916. The Schneider CA1 first fought at Berry-au-Bac on April 16, 1917, where 57 of 132 were lost, many burned. The lighter Renault FT did better.
When and how
Le Creusot and Paris, 1915–17; Estienne and Brillié; Berry-au-Bac, on the Chemin des Dames front, April 16, 1917.
How we know
French army orders, Estienne's reports and battle records; a surviving Schneider CA1 is displayed at the French tank museum in Saumur.
Debates and open questions
Loss figures for Berry-au-Bac vary by source. France and Britain developed tanks separately, and credit for the idea has long been argued.
▸Chrysler's Detroit Arsenal Tank Plant (M4 Sherman) built about a quarter of America's wartime TankMostly agreed
The connection
Starting with the M3 Lee in 1941, Chrysler's arsenal applied car-industry assembly methods to tanks, then turned out M4 Shermans in huge numbers. Its 22,234 tanks were roughly a quarter of the 88,000 or so the US built in the war, many shipped to Britain and the Soviet Union under Lend-Lease.
When and how
Warren, Michigan, 1941–1945; Chrysler managers under company president K.T. Keller, working with the Army's Ordnance Department.
How sure are we?
Army ordnance production records and Chrysler's wartime reports; national totals differ slightly by source and by what counts as a tank.
Debates and open questions
The Sherman's armor and fire risk are still debated: critics call it outclassed, defenders cite its reliability, numbers and ease of repair.
▸Soviet factory evacuation and 'Tankograd' mass-produced the T-34, most-built wartime TankWell documented
The connection
The T-34, with sloped armor, a 76 mm gun and wide tracks for mud and snow, was simple enough to mass-produce. Ural plants sharply cut the labor hours needed for each tank and built it by the tens of thousands. About 57,000 were made in 1940–45, more than any other tank of the war.
When and how
Nizhny Tagil, Chelyabinsk, Omsk, Sverdlovsk and Gorky, 1941–45; designers Mikhail Koshkin, who died in 1940, and Alexander Morozov.
How we know
Soviet factory records and many surviving T-34s, including at the Kubinka tank museum near Moscow.
Debates and open questions
Western legend made the T-34 a perfect design; recent studies stress its poor visibility, cramped crew and rushed quality, and debate its real edge.