The 'Bratislava-Brno Offensive Operation' was a Soviet undertaking in the western part of Slovakia and southern Moravia by the forces of the 2^nd Ukrainian Front in order to capture Bratislava and Brno, the capitals of Slovakia and Moravia respectively (25 March/5 May 1945).

In the spring of 1945, the Soviets launched a series of major offensives on the southern sector of the Eastern Front. On 10 March, General Ivan Ye. Petrov’s 4^th Ukrainian Front began the 'Moravia-Ostrava Offensive Operation' and on 15 March Marshal Sovetskogo Soyuza Fedor I. Tolbukhin’s 3^rd Ukrainian Front began the 'Vienna Strategic Offensive Operation'. Marshal Sovetskogo Soyuza Rodion Ya. Malinovsky’s 2^nd Ukrainian Front, which was located between the 3^rd Ukrainian Front and the 4^th Ukrainian Front, was assigned the task of taking Bratislava and Brno.

The 2^nd Ukrainian Front, commanded by Malinovsky with General Polkovnik Matvei V. Zakharov as its chief-of-staff, comprised General Polkovnik Mikhail S. Shumilov’s 7^th Guards Army, General Leytenant Filipp F. Zhmachenko’s 40^th Army, General de corp de armatâ Nicolae Dăscălescu’s Romanian 4^th Army, General Leytenant Ivan M. Managarov’s 53^rd Army, General de corp de armatâ Vasile Atanasiu’s Romanian 1^st Army, General Leytenant Issa A. Pliyev’s 1^st Guards Cavalry Mechanised Group, General Polkovnik Sergei K. Goryunov’s 5^th Air Army, Kontr Admiral Georgi Kholostyakov’s Danube River Flotilla, from 16 April General Polkovnik Andrei G. Kravchenko’s 6^th Guards Tank Army.

The German forces facing the onslaught of these Soviet and allied formations were elements of General Otto Wöhler’s (from 6 April Generaloberst Dr Lothar Rendulic’s) Heeresgruppe 'Süd' in the form of General Hans Kreysing’s 8^th Army (Generalleutnant Werner Schmidt-Hammer’s LXXII Corps, General Kurt Röpke’s XXIX Corps, General Kurt Versock’s [from 20 April General Arthur Kullmer’s]) XLIII Corps and General Ulrich Kleemann’s Panzerkorps 'Feldherrnhalle'; and elements of Generalfeldmarschall Ferdinand Schörner’s Heeresgruppe 'Mitte' in the form of General Walther Nehring’s 1^st Panzerarmee. Air support was provided by Generaloberst Otto Dessloch’s Luftflotte IV.

At the beginning of the offensive Shumilov’s 7^th Guards Army, in a surprise night attack, broke through defences of Generalleutnant Fritz Bayer’s 153^rd Division and Generalleutnant Josef Rintelen’s 357^th Division on the Hron river. The breakthrough had a width of 11 miles (17 km) and within two days the army had advanced about 22 miles (35 km) to the west in the direction of Nové Zámky. The 7^th Guards Army then swiftly pushed cross the Danube river lowlands toward Bratislava. The advance of General Leytenant Ivan M. Managorov’s 53^rd Army in central Slovakia was slower as a result of the hilly terrain it had to cover, and the movement of General Leytenant Filipp F. Zhmachenko’s 40^th Army was still slower as it was operating in the mountains. However, on 26 March Dăscălescu’s Romanian 4^th Army liberated Banská Bystrica, the centre of the Slovak National Uprising that had been defeated in the previous year.

On 2 April the battle of Bratislava started when Soviet units captured the city’s airport at Vajnory. President Jozef Tiso and the government of the Slovak puppet state had already left the capital, and by 5 April had found asylum in Austrian monastery of Kremsmünster. The defence of Bratislava rested in the hands of General Hermann Balck’s German 6^th Army and Vezérezredes József Heszlény’s Hungarian 3^rd Army of Rendulic’s Heeresgruppe 'Ostmark' created on 30 April by the renaming of Heeresgruppe 'Süd '. On the night of 3 April, the Germans destroyed all the major bridges across the Danube river. With the support of the 27^th Tank Brigade and the Danube River Flotilla, Soviet troops of the 7^th Army’s XXIII Corps and XXV Guards Corps drove the German troops out of the city, and Bratislava was in Soviet hands by the evening of 4 April during the operation’s second week. The districts of the city on the southern bank of the Danube river were captured on the following day by the X Guards Corps of the 46^th Army, which was also part of the 2^nd Ukrainian Front, but because it fought on other side of the Danube river from the rest of the front, for most of the time it was committed in the 3^rd Ukrainian Front’s 'Vienna Strategic Offensive Operation'.

The Czechoslovak government and president then moved to Bratislava on 8 May.

The next main obstacle to continued Soviet advance was the Slovak-Moravian border created by the Morava river, which in the area between Devín and Hodonín was surrounded by the forests and wetlands on each side of the river. In the spring the flooded area was as much as 5 miles (8 km) wide, but despite this on 6 April the first reconnaissance units of the VI Guards Cavalry Corps made a crossing and on the next day secured the damaged bridge and railway embankment: the latter was the only area above the water. The fighting for the town of Lanzhot was heavy and lasted for four days as the already strong German defence was bolstered by more than 60 tanks, including a number of PzKpfw VI Tiger II heavy tanks. Lanzhot was finally liberated on 11 April after one-quarter of its housing stock had been completely destroyed and another three-fifths damaged. The Soviet cavalry formation lost nearly 1,500 men and 2,000 horses, mostly as the result of long immersion in cold water. The 53^rd Army meanwhile crossed the Morava river near Hodonín, and this latter was liberated early on 13 April. The 53^rd Army lost about 350 men during the crossing, and the Germans about 130 men. At this time, the 40^th Army on the right flank was still fighting in Slovak mountains, and on 10 April liberated the town of Trenčín and managed to cross the Váh river to the south of the town despite the fact that all of the bridges been destroyed by the Germans as they retreated. Trenčín then became 'front city', and its districts behind the river were not liberated until 29 April.

After the breakthrough on the Morava river, Soviet units of the VII Mechanised Corps advanced rapidly to the Jihlava river, where they met Generalmajor Günther Pape’s Panzerdivision 'Feldherrnhalle 1'. On 18 April Schörner, the commander of Heeresgruppe 'Mitte', ordered the dismantling of the defences of Festung 'Brno' so that its defenders could advance and meet the Soviets on the approaches to the city: the Soviet advance was halted at Rajhrad, some 9 miles (15 km) to the south of Brno. Soviet units outflanked the Germans, however, and continued farther to the west, and by 22.00 on the same day had reached the church of small village Ořechov, less than 7.5 miles (12 km) from the outskirts of Brno, which thus within range of Soviet artillery. The reconnaissance units of the VII Mechanised Corps penetrated farther to the north-west and captured several villages, including Popůvky. Some Soviet light tanks reached the outskirts of Brno, but were soon destroyed.

Because the Panzerdivision 'Feldherrnhalle 1' was behind the Jihlava river in an area defended only by Waffen-SS training units and Volksturm militia, the armour of Oberst Kurt Treuhaupt’s 16^th Panzerdivision was summoned to provide greater strength in a counterattack. In the evening of 19 April, German tanks and assault guns quickly penetrated the lines of exhausted Soviet soldiers, with close-range fire destroyed many Soviet tanks, and recaptured the village of Ořechov and nearby hillock with its church. On the next day, armour of the 16^th Panzerdivision attacked toward the position of the Panzerdivision 'Feldherrnhalle', and working together the two German armoured divisions cut off and surrounded the Soviet reconnaissance elements at Popůvky. The Germans lacked sufficient strength to complete the destruction of the encircled Soviet units, however. Moreover, Treuhaupt was captured by Czech partisans, and this exercised a seriously adverse effect on the division’s capacity to co-ordinate its activities with those of other German elements.

During the night of 23/24 April, the VII Mechanised Corps launched a renewed attack and relieved the encircled units, and on the next day once more liberated Ořechov. In all, the battle of Ořechov lasted for seven days, in which the Soviets lost 960 men and 35 armoured vehicles. The Germans had lost between 275 and 300 men, as well as about 30 armoured vehicles. The village of Ořechov had suffered 23 casualties and four-fifths of its houses had been destroyed.

The revived Soviet assault was supported by Kravchenko’s 6^th Guards Tank Army, which had just arrived to the rear of the 53^rd Army after the fall of Vienna. While the 1^st Guards Mechanised Cavalry Group renewed its attack on Brno, the 53^rd Army attacked to the east of Brno, advancing toward Slapanice and Slavkov. The 53^rd Army’s advance broke through the German lines and the 6^th Guards Tank Army advanced through the gap in the evening of 23 April. By the evening of 25 April the army’s tanks had reached the outskirts of Brno from the east, while the 1^st Guards Mechanised Cavalry Group reached Brno from the south. The next morning the city centre was liberated and by 12.00 the Spilberk Castle, which until then had served as the Gestapo prison in Brno, was also in Soviet hands.

Thus Brno was largely liberated on 26 April, though some of its northern districts were in German hands until 5 May. In the days following the liberation of Brno, armies of 2^nd Ukrainian Front secured the front line to the west and expanded to the north to meet the forces of the 4^th Ukrainian Front and thus to outflank Nehring’s 1^st Panzerarmee. However, after the start of the Prague uprising, the Stavka changed its plan and ordered the 2^nd Ukrainian Front to join the 'Prague Offensive Operation'. Meanwhile, the Romanian 1^st and 4^th Armies both advanced along the Morava river and before the end of the war liberated the towns of Otrokovice, Kroměříz and Prostějov.

During the offensive, the Soviet forces had suffered casualties of nearly 17,000 men killed. Soviet sources reported that they had destroyed nine German divisions. The offensive had reportedly created the operational conditions required for the 'Prague Offensive Operation' as it had outflanked Heeresgruppe 'Mitte' from the south.

It is worth noting that within the 53^rd Army was the Czechoslovak Special Purpose Company, whose task it was to capture and secure the buildings in Brno for the needs of the Soviet-supported Czechoslovak government. However, because of the rapid end of war the government had relocated from Bratislava directly to Prague on 10 May. President Edvard Benes spent almost a week in liberated Brno before he joined the government in Prague.