Gorlice–Tarnów Offensive

Background

By the spring of 1915 the Austro-Hungarian army was close to breaking. Its winter offensives in the Carpathians had failed at appalling cost, Przemyśl had surrendered to the Russians in March, and Russian troops were pushing through the mountain passes towards the Hungarian plain. Half the army that had gone to war in 1914 had become casualties. Italy looked likely to join the Allies. In April Conrad von Hötzendorf, the Austro-Hungarian chief of staff, asked again for German divisions, and threatened a separate peace if they did not come.

Both high commands had settled independently on the same answer: a break-through between the Vistula and the Carpathians, where the Russians had thinned their line to feed the mountain fighting. A drive from Gorlice towards Sanok would get behind the Russian armies in the Carpathians and roll them up. On 13 April Erich von Falkenhayn, the German chief of the general staff, proposed sending an army of at least eight German divisions with strong artillery to advance from the line Gorlice–Gromnik. The two chiefs agreed the plan in Berlin on 14 April. Who first had the idea is still argued over: Polish and Austrian writers credit Conrad, others Falkenhayn.

The price for Conrad was command. The new German 11th Army, under August von Mackensen with Colonel Hans von Seeckt as chief of staff, took the Austro-Hungarian 4th Army under its orders; Falkenhayn's instructions went through the Austro-Hungarian high command. The Germans came east in about 500 trains. Diversions kept Russian eyes elsewhere: a German raid into Courland, demonstrations elsewhere on the front, and, in the west, the first gas attack at Ypres on 22 April. Local people were moved out of the assembly area.

The armies

Mackensen's 11th Army lined up, south to north, Korps Kneussl (the 11th Bavarian and 119th Divisions), François's XLI Reserve Corps opposite Gorlice, Arz's Austro-Hungarian VI Corps and Plettenberg's Guards Corps, with Emmich's X Corps in reserve. The German divisions were new formations of three regiments, with four-gun batteries, made by stripping divisions in the west. VI Corps included the 12th 'Kraków' Division, largely Polish. The Austro-Hungarian 4th Army stood to the north as far as the Vistula, and Boroević's X Corps to the south on the Magura Małastowska. In all, about 217,000 men were set against the breakthrough.

The edge was artillery. Ziethen's heavy train included the German and Austro-Hungarian siege mortars that had broken the Belgian forts. On the main sector Mackensen had 457 light and 159 heavy guns and 96 mortars against 141 light and 4 heavy Russian guns. Aircraft directed the fire and field telephones went forward with the infantry. Each German division got 200 light Austro-Hungarian wagons for the poor roads.

Radko Dimitriev's 3rd Army had about 219,000 men, but was spread from the Vistula to the Łupków pass and worn out by the winter. Its divisions were under strength, and its guns were rationed to about ten rounds per battery a day. The trenches, dug over months, ran in several lines; how strong they were is disputed. The 3rd Caucasian Corps lay in reserve near Jasło.

The battle

This page follows CDB90's engagement 'Gorlice–Tarnów (opening phase)', 2–5 May, and then the pursuit to the San, 6–12 May.

1–2 May: the bombardment. Ranging fire began on 1 May. That night Stöger-Steiner's combined division slipped across the lower Dunajec at Otfinów. At 6 a.m. on 2 May the guns of three armies opened the main bombardment, the heaviest yet seen in the east; the heavy mortars joined at 9 a.m. Colonel Franciszek Latinik of the 100th Regiment wrote that the shells threw 'soil, rocks, beams, rifles, and human bodies high up into the air'. The Russian artillery barely replied. At 10 a.m. the fire lifted to the rear and the infantry went in.

2 May: Pustki, Zamczysko and Gorlice. The first trenches fell easily, but lines hidden in the woods had survived. On Pustki hill above Łużna the 56th and 100th Regiments of the Kraków Division took two lines without loss, then fought with the bayonet; the hill fell at about 11 a.m., for nearly 900 dead. To the south the Bavarians attacked the height Mackensen called Zameczyka, 250 m above them, 'a veritable fortress', and took the first Russian position only towards evening after several assaults. At Gorlice, François's men reached the cemetery but stuck in street fighting until a fresh bombardment drove the defenders out; a Bavarian patrol reached the square at about 3.30 p.m. On the Austro-Hungarian wings, the 3rd Army's X Corps stormed the heights east of Małastów by 5 p.m., while the 4th Army fought hard for the Dobrotyn ridge.

The main blow fell on the Russian X Corps (Protopopov), with the 9th, 31st and 61st Divisions. At 5.42 p.m. Protopopov allowed a retreat at nightfall, but Dimitriev refused and ordered the line held. By 8 p.m. the corps had been broken, the heights lost and its reserves used up; to the north the 70th Division of IX Corps had also given way. The Central Powers took some 17,000–20,000 prisoners that day.

3–4 May: the counter-attack fails. Mackensen put the 11th Bavarian, 20th and 119th Divisions under Emmich and pressed on. The 4th Army's XIV Corps stormed hills 419 and 402; the 11th Army reached Biecz. Dimitriev threw in the 3rd Caucasian Corps piecemeal under Irmanov. Its counter-attack at Cieklin on 4 May broke several German battalions but was repelled by noon, and the Germans broke through at its junction with the 24th Corps. The second and third Russian positions gave way, and the attack spread along the whole front of Boroević's 3rd Army.

5 May. The Grand Duke forbade any withdrawal, but Emmich drove the Russians back behind the Jasiołka towards Dukla, and the Russian 24th and 12th Corps in the mountains began to yield. At 11 p.m. Dimitriev's headquarters ordered the whole army back. CDB90's engagement ends here.

6–12 May: to the San. The Russians gave up Tarnów; near Tylawa the Austro-Hungarian X Corps and Berndt's cavalry trapped most of Kornilov's 48th Division. Reinforcements were fed in by division. A counter-attack by the Russian 21st Corps on 10 May threw back the 11th Bavarians, but the line around it collapsed, and that afternoon Dimitriev ordered a retreat to the San. By the evening of 11 May the Russians were behind it, and Rzeszów fell during the night of the 12th. The Central Powers counted 130,000–140,000 prisoners.

Aftermath

The Russian 3rd Army was wrecked. By about 11 May, on Buttar's account, its X and 24th Corps had effectively ceased to exist and IX Corps had lost 80 per cent of its strength. Many divisions were down to about 1,000 men. No reliable count of the killed and wounded exists for these ten days; prisoners alone ran to 130,000–140,000. Central Powers losses are put at 37,000–90,000.

The offensive went on. The Guards stormed the bridgehead at Jarosław on 15 May. Przemyśl was retaken on 3 June and Lemberg on 22 June, and the Galician oil fields came back into production. Dimitriev was dismissed and replaced by Lesh. Mackensen was made a field marshal. In July the Central Powers turned north, and in the Great Retreat the Russians gave up Poland; Warsaw fell on 5 August. Russian losses from 2 May to 13 July are put at about a million men, the Central Powers' at about 490,000.

It was one of the few breakthroughs of the war that turned into a new strategic situation, and it ended any Russian threat to Hungary. Arguments continue over who conceived it, and over why the Russians lost: their shell shortage and the enemy's artillery, or, as Zayonchkovski argued, poor command that fed in reserves piecemeal and refused to retreat. In Poland it is sometimes called the 'little Verdun'. The war cemeteries of the Gorlice district, including the one on Pustki, are its memorial, and since 2010 a re-enactment has been held at Sękowa.

Wargaming it

The opening day is an excellent grand-tactical game: about 35–40 km of foothills, with battalions or regiments as units and turns of an hour or two. It is a set-piece attack, so the interest lies in what the bombardment leaves behind. Hidden Russian lines in the woods, and strongpoints such as Pustki, Zamczysko and the Gorlice cemetery, should be resolved by uncertain artillery results; the attacker should not know which positions have survived until the infantry reach them.

For 2–12 May an operational game at division level works better, with simple rules for supply, road movement and the reorganisation of broken formations. Mackensen's directive suits the attacker: corps were told to push as far as they could without waiting for neighbours, and the game should reward exploiting a sector that has broken rather than keeping the line straight. The Russian player has to decide when to retreat, and should be bound by Stavka's orders to hold, with reserves arriving piecemeal and late. Russian guns should be strictly limited in ammunition.

Good 'what ifs': Dimitriev lets X Corps fall back on the night of 2 May; the 3rd Caucasian Corps is held for a single co-ordinated counter-attack; Stavka allows a retreat to the San on 5 May, as the front staff urged; the Russians spot the German build-up in time to reinforce the sector. A campaign game can carry on to Przemyśl and Lemberg.

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.