The 'Battle of the Seelow Heights' was fought between Soviet and German forces within the 'Berlin Strategic Offensive Operation' (16/19 April 1945).

This was one of the last assaults on major entrenched defensive positions in World War II, and was fought over a period of three days. Almost 1 million men of Marshal Sovetskogo Soyuza Georgi K. Zhukov’s 1^st Belorussian Front (including 78,556 men of the Polish 1^st Army) attacked the position known as the 'Gates of Berlin'. They were opposed by about 110,000 men of General Theodor Busse’s 9^th Army, which was a component of Generaloberst Gotthard Heinrici’s Heeresgruppe 'Weichsel'. This battle is often seen as part of the 'Battle of the Oder-Neisse', and the Seelower Höhen (Seelow Heights) was the area in which some of the most bitter fighting in the overall battle took place, but was only one of several crossing points along the Oder and Neisse rivers along which the Soviets attacked. The 'Battle of the Oder-Neisse' was itself only the opening phase of the 'Battle of Berlin'.

The result was the encirclement of the 9^th Army and the consequent 'Battle of Halbe'.

The fall of Königsberg in East Prussia on 9 April made Marshal Sovetskogo Soyuza Konstantin K. Rokossovsky’s 2^nd Belorussian Front available for movement to the eastern bank of the Oder river, and in the course of the first fortnight of April, the Soviets performed their fastest front redeployment of the war. The 2^nd Belorussian Front relieved the 1^st Belorussian Front along the lower reaches of the Oder river between Schwedt and the Baltic Sea. This allowed the 1^st Belorussian Front to concentrate in the southern half of its former front, opposite the Seelow Heights. To the south, Marshal Sovetskogo Soyuza Ivan S. Konev’s 1^st Ukrainian Front shifted its main strength from Upper Silesia north-west to the Neisse river. The three Soviet fronts together had 2.5 million men, 6,250 tanks, 7,500 aircraft, 41,600 pieces of artillery and mortars, 3,255 truck-mounted Katyusha rocket launchers and 95,383 motor vehicles.

The 1^st Belorussian Front had nine infantry and two tank armies totalling 77 infantry divisions, two cavalry corps, five tank corps, two mechanised corps, eight artillery divisions, one guards mortar division and a mix of other artillery and rocket-launcher brigades. The front had 3,059 tanks and self-propelled guns and 18,934 pieces of artillery and mortars.

Eight of the 11 Soviet armies were positioned along the Oder river. In the north, General Polkovnik Pavel A. Belov’s 61^st Army and General Leytenant Stanislav Poplavsky’s 1^st Polish Army held the river line from Schwedt to its meeting with the Finow Canal. In the Soviet bridgehead at Küstrin, General Franz I. Perkhororoch’s 47^th Army, General Polkovnik Vasili I. Kuznetsov’s 3^rd Shock Army, General Polkovnik Nikolai Ye. Berzarin’s 5^th Shock Army and General Polkovnik Vasili I. Chuikov’s 8^th Guards Army were concentrated for the attack toward eastern Berlin. General Leytenant Vladimir Ya. Kolpatchy’s 69^th Army and General Polkovnik Vyacheslav D. Tsvetayev’s 33^rd Army covered the river line to the south as far as Guben. General Polkovnik Mikhail Ye. Katukov’s 1^st Guards Tank Army, General Polkovnik Semyon I. Bogdanov’s 2^nd Guards Tank Army and General Polkovnik Aleksandr V. Gorbatov’s 3^rd Army were in reserve. The 5^th Shock Army and 8^th Guards Army were positioned directly opposite the strongest part of the German defences, where the Reichsstraße 1 to Berlin passed across the heights.

The 9^th Army held the length of the Eastern Front between Finow Canal and Guben, an area which included the Seelow Heights. It had 14 divisions, the Festung 'Frankfurt', 587 tanks (512 operational, 55 in repair and 20 in transit) and 2,625 pieces of artillery including 695 anti-aircraft guns. Farther to the south, the front was held by General Fritz-Hubert Gräser’s 4^th Panzerarmee against the 1^st Ukrainian Front.

Heinrici had replaced Reichsführer-SS Heinrich Himmler as commander of Heeresgruppe 'Weichsel' on 20 March, and rightly predicted that the main Soviet thrust would be made across the Oder rover and along the Reichsstraße 1 at Seelow Heights. He decided to defend the river’s western bank with only a light skirmishing screen, but build strong fortifications on the Seelow Heights, which rise about 157 ft (48 m) above the Oder river and overlook this river at the point where the Reichsstraße crossed it. He thinned his line in other areas in order to be able to place more men on the heights.

The Oder river’s flood plain was already saturated as a result of the spring thaw, but German engineers had released additional water from a reservoir upstream of the threatened area, and this had turned the plain into a swamp. Behind the heights, military engineers built three lines of defences, reaching back toward Berlin. The last was the 'Wotan-Linie' some 10 to 15 miles (16 to 24 km) behind the front line. These defensive lines comprised anti-tank ditches, anti-tank gun emplacements, and an extensive network of trenches and bunkers.

Early on 16 April, the Soviet offensive started with a massive bombardment by thousands of artillery pieces and Katyusha rocket-launchers. Well before dawn, the 1^st Belorussian Front attacked across the Oder river and the 1^st Ukrainian Front attacked across the Neisse river. The 1^st Belorussian Front was the stronger of the two huge Soviet formations, but had the more difficult task as it was facing the bulk of the German forces.

The 1^st Belorussian Front’s assault started with an intense artillery bombardment. According to historians, Heinrici and Busse had anticipated the attack and withdrawn their defenders from the first line of trenches just before the Soviet artillery obliterated them, but according to a report to Stalin, Zhukov wrote that 'Considering that the enemy might move its infantry from the first to the second and third lines of trenches in the morning, I used a nightly artillery barrage with a high density of fire for 30 minutes, with the use of searchlights to blind the enemy and light the terrain ahead of the advancing troops…According to the interrogation of prisoners, the artillery fire was so sudden and overwhelming that the enemy did not have time to move from the first trench line; the second and third lines were at all times under heavy fire from our artillery. As a result of this, the enemy units in the first line of defence suffered heavy casualties.'

The swampy ground proved to be a great hindrance to the Soviet advance, and a German counter-barrage caused heavy Soviet casualties. Frustrated by the slow advance, Zhukov committed his reserves, which according to his earlier plan was to have been held back until the expected breakthrough. By a time early in evening, an advance of 2.5 to 3.7 miles (4 to 6 km) had been achieved: the VII Corps of the 3^rd Shock Army had advanced 5 miles (8 km), but the second German defensive line remained intact. Zhukov was forced to report that his battle was not proceeding as smoothly as planned. However, in the south the attack by Konev’s 1^st Ukrainian Front was going according to plan. To spur Zhukov, Stalin informed him that he was allowing Konev to direct his tank armies north toward Berlin.

On 17 April, the 1^st Belorussian Front’s troops continued to advance in accordance with the initial plan, and by the fall of night the German second defensive line, the Stein Stellung, had been penetrated by the 5^th Shock Army and 2^nd Guards Tank Army. The right flank of the IV Guards Corps of the 8^th Guards Army, together with the XI Guards Tank Corps of the 1^st Guards Tank Army, had exploited the success of their comrades and also advanced. The 47^th Army and the 3^rd Sock rmy moved forward and other 2.5 to 5 miles (4 to 8 km).

To the south, however, the 1^st Ukrainian Front was driving back the 4^th Panzerarmee, and the left wing of Generalfeldmarschall Ferdinand Schörner’s Heeresgruppe 'Mitte' was starting to crumble. Schörner kept his two reserve Panzer divisions in the south to cover his centre, instead of using them to shore up the 4^th Panzerarmee, and this proved to be the turning point in the 'Berlin Strategic Offensive Operation' because the positions of both Heeresgruppe 'Weichsel' and the central and right-hand sectors of Heeresgruppe 'Mitte' were rapidly becoming untenable and, unless they fell back in line with the 4^th Panzerarmee, faced envelopment. In effect, Konev’s successful attack on Schörner’s relatively poor defences to the south of the Seelow Heights was unhingeing Heinrici’s defence.

On 18 April, both Soviet fronts advanced despite suffering heavy losses. The Seelow Heights area was bypassed from the north, where the Soviet forces met counterattacks by German reserves in the form of SS-Brigadeführer und Generalmajor der Waffen-SS Joachim Ziegler’s 11^th SS-Freiwilligen Panzergrenadierdivision 'Nordland', SS-Brigadeführer und Generalmajor der Waffen-SS Jürgen Wagner’s 23^rd SS-Freiwilligen Panzergrenadierdivision 'Nederland' (niederlandische Nr 1) and SS-Sturmbannführer Paul Kausch’s 503^rd schwere SS-Panzerabteilung. By the fall of night, an advance of between 1.9 and 3.1 miles (3 and 5 km) on the right flank and between 1.9 and 5 miles (3 and 8 km) in the centre had been achieved, and the 1^st Belorussian Front had reached the third and final German defence line.

On 19 April, the 1^st Belorussian Front eventually broke through the final defence line on the Seelow Heights and nothing but broken German forces now lay between its formations and Berlin. The remnants of the 9^th Army and the 4^th Panzerarmee were enveloped by the 1^st Belorussian Front and elements of the 1^st Ukrainian Front which had broken through and turned north. Other armies of the 1^st Ukrainian Front raced to the west toward a junction with US forces advancing to the east. By the end of 19 April, the German front line in the east had effectively ceased to exist, and all that remained were isolated pockets of resistance.

The line on the Seelow Heights had been the last major defensive line to the east of Berlin. From 19 April, the road to Berlin, some 56 miles (90 km) to the west, lay open to the Soviets. By 23 April, Berlin had been fully encircled and the 'Battle in Berlin' began. Within two weeks, Adolf Hitler had committed suicide and the war in Europe was effectively over.

As result of the 1^st Belorussian Front’s success at the Seelow Heights, and the Oder river front in general, most of the surviving formations and units of the 9^th Army were encircled before they could retreat to Berlin. The city was then defended only by broken formations, the Volkssturm, police, and air-defence units, and was taken by the Soviets within 10 bloody and destructive days.

After the war, critics of Zhukov claimed that he should have stopped the 1^st Belorussian Front’s attack via the direct Autobahn route to Berlin and instead made use of the 1^st Ukrainian Front’s breakthrough over the Neisse river and concentrated his front’s armies on surrounding Berlin from the north. This would have bypassed the strong German defences on the Seelow Heights, and thereby avoided many casualties and the delay in the advance on Berlin. Zhukov supposedly took the shortest path, his critics contended, so that his troops would beat those of Konev for the honour of being the first Soviet troops to enter the city. However, Zhukov had chosen to deliver his main thrust through the Seelow Heights not because he believed that this was the quickest way to Berlin, but because he thought that was the quickest way to link with Konev’s 1^st Ukrainian Front and cut off the 9^th Army from the city. Moreover, bypassing the Seelow Heights and attacking Berlin from the north would have exposed the northern flank of the 1^st Belorussian Front to the possibility of an offensive from German forces to the north, which could have pinned Zhukov’s formations against the Seelow Heights. Furthermore, only two of the 1^st Belorussian Front’s five armies actually attacked the Seelow Heights proper, and the heights were eventually bypassed from the north as soon as there was a narrow breakthrough.

Estimates of Soviet casualties during the assault on the Seelow Heights vary from less than 10,000 to more than 30,000 men killed.