Battle of Tannenberg (1914)

Background

Germany went to war in August 1914 with seven of its eight armies in the west. The Schlieffen Plan gambled that France could be beaten before Russia's slow mobilisation was complete, and East Prussia was left to the Eighth Army under Maximilian von Prittwitz. Russia moved faster than expected. To take pressure off France, General Yakov Zhilinsky's North-Western Front sent two armies into East Prussia. Rennenkampf's First Army came from the east, and Samsonov's Second Army came north from the Narew in Russian Poland. The Masurian Lakes kept the two armies apart.

On 20 August Rennenkampf beat the Germans at Gumbinnen. Prittwitz talked of falling back behind the Vistula, and Moltke replaced him. The new commander was Paul von Hindenburg, a 66-year-old general brought out of retirement, with Erich Ludendorff, fresh from the storming of Liège, as his chief of staff. They reached the front on 23 August.

A counterstroke was already taking shape. Rennenkampf had paused after Gumbinnen, and the Eighth Army's operations officer, Lieutenant-Colonel Max Hoffmann, proposed leaving only a cavalry screen in front of him. Every other formation would go south-west against Samsonov's exposed army, using East Prussia's railways and roads to get there first. Ludendorff, travelling east, had reached much the same conclusion. Who thought of it first is still argued over. The battle would be fought in the lake-and-forest country between Allenstein, Hohenstein and Neidenburg, where Samsonov's corps, already strung out and short of supplies, were marching north.

The armies

The German Eighth Army brought four corps against Samsonov. Scholtz's XX Corps was already in front of him. François's I Corps came round by rail from the Gumbinnen front to the right flank, a journey s3 puts at about 200 miles. Mackensen's XVII Corps and Below's I Reserve Corps marched south-west from the Rennenkampf front. Reserve and Landwehr formations filled the gaps. These were well-trained peacetime regulars and reservists. They fought on home ground they had exercised over, with plentiful heavy artillery and dense rail and road links behind them.

The Russian Second Army had XV (Martos), XIII (Klyuev) and XXIII Corps in the centre, I Corps (Artamonov) on the left and VI Corps (Blagoveshchensky) out on the right. Its soldiers were brave and could fight hard, as XV Corps showed. The army as a whole, however, had been hurried forward before it was ready. Only two railways reached the frontier, and they ran on a different gauge, so supplies came forward on sandy tracks. Units arrived tired and hungry. Staff work was poor, and communications were worse. Samsonov's headquarters had no proper cipher system, so orders went out by wireless in plain text, and the Germans read them. Above him, Zhilinsky, who never came near the battle, kept pressing him to advance faster.

The battle

Opening moves, 23–25 August. Samsonov's corps crossed the frontier and pushed north. On 24 August Scholtz's XX Corps checked them around Orlau and Frankenau, then fell back towards Tannenberg. That day the Germans picked up uncoded Russian wireless messages. One showed that Rennenkampf was not marching to Samsonov's aid. Another gave the line of Samsonov's advance. With them, the German command could leave Rennenkampf to the cavalry. Ludendorff ordered François to attack the Russian left at Usdau at once. François protested that much of his artillery was still on the trains, but promised that if it was ordered, an attack would be made. His preliminary attack took the high ground at Seeben.

The flanks give way, 26–27 August. On 26 August, 30–40 km to the north-east, Mackensen's XVII Corps and Below's I Reserve Corps struck the isolated Russian VI Corps near Bischofsburg and drove it back towards the border. That stripped Samsonov of his right flank. In the centre, meanwhile, Martos's XV Corps and Klyuev's XIII Corps were still attacking north towards Hohenstein and Allenstein, and Martos badly mauled the German 41st Division. Neither Russian commander knew what was happening on his flanks. On 27 August François, with his guns now up, took Usdau after a heavy bombardment. Artamonov's I Corps fell back on Soldau, and the Russian left collapsed in turn. That evening Ludendorff gave his orders for the encirclement.

Closing the ring, 28–29 August. On 28 August German airmen reported that Rennenkampf was moving towards the Eighth Army's rear. Hindenburg held his nerve and kept to the plan. François ignored orders to turn north. Instead he drove east along the frontier road through Soldau to Neidenburg, across the Russian line of retreat. Samsonov ordered a general withdrawal, but it came too late. On 29 August François's troops pushed on towards Willenberg and linked up with Mackensen's XVII Corps coming from the north. Sources place the meeting at Willenberg or Jedwabno. XV Corps, XIII Corps and part of XXIII Corps were trapped in the forests between Hohenstein, Neidenburg and Willenberg, a pocket s1 centres on Frogenau. Columns that tried to break south down the forest roads ran into machine-gun and artillery fire at the exits.

The end, 29–30 August. Russian troops outside the ring tried to break in and failed. Inside it, units broke up into hungry groups that surrendered in thousands. Samsonov had gone forward to his corps and lost touch with his own headquarters. With a handful of staff officers he set off on foot through the woods towards the frontier. On the night of 29–30 August he walked away from them and shot himself. By 30 August the Second Army's centre had ceased to exist. Moltke had already taken two corps from the Western Front to reinforce the east, and they arrived after the battle was won.

Aftermath

The Second Army lost about 120,000 men, most of them prisoners, along with some 500 guns. s1 says 13 generals were captured. German losses were nearer 13,000–15,000. The trophies are said to have filled 60 trains. The victory was not decisive. A week later, at the First Battle of the Masurian Lakes, the reinforced Eighth Army turned on Rennenkampf and drove him out of East Prussia, but Russia stayed in the war. Russian defeats in East Prussia were also offset by Russian victories over Austria-Hungary in Galicia.

The myth mattered as much as the victory. Hindenburg asked for the battle to be named after Tannenberg, a village west of the main fighting, near the site where the Teutonic Knights had been defeated by Poland–Lithuania in 1410. Both Ludendorff and Hoffmann later claimed the idea. The name presented the battle as revenge for 1410. Hindenburg became a national hero, and the reputation took him to the supreme command and, in 1925, the presidency. Hoffmann's planning and François's disobedience went largely unsung, while Ludendorff in his memoirs claimed the encirclement as his own. Historians still argue over how the credit should be shared among the four.

A vast memorial at Hohenstein was completed in 1927, and Hindenburg was buried there in 1934. Retreating German troops blew it up in January 1945. In Russia, Tannenberg became a byword for the incompetence of the Tsarist high command.

Wargaming it

Tannenberg is a pure manoeuvre battle. It suits operational games at division or brigade level, with turns of half a day to a day and hexes or grid squares of 2–5 km. A board running from Allenstein and Bischofsburg south to the frontier at Soldau and Willenberg holds all of it. The lakes, the forests and the few roads through them channel both sides and set the pace. Tactical games can take single actions: Usdau on 27 August, the destruction of VI Corps on 26 August, or Martos against the 41st Division.

The interesting rules are about information and command, more than firepower. The German player should see much of the Russian plan, as the intercepts allowed. The Russian player should be blind, slow to resupply and liable to lose contact between corps. Rennenkampf is the great uncertainty. A variable entry for the First Army forces the German player to judge, as Hindenburg had to, how long the screen can hold. Rules for subordinate initiative let François either win the battle or wreck the plan.

The what-ifs follow from these. Rennenkampf marches south-west on 26 August. The Russians encipher their signals. Samsonov halts and pulls back on 26 August rather than pressing north. François obeys the order to turn north and leaves the southern exits open. Each of them tests how near the Germans came to a far more dangerous battle.

Maps and pictures

Pictures from the time

Photographs by the armies' photographers and the press, and drawings made at the time: free-to-use pictures from the battle's category on Wikimedia Commons. Each opens its file page there, with the full caption and source.