In one week in September, Ukrainian forces liberated 1,100 square miles in Northeastern Ukraine. This is more than Russia’s military managed to seize in months of costly attritional warfare in the Donbas region. Further withdrawals announced by Russia’s Defense Ministry may result in over 3,200 square miles falling back under Ukrainian control.
Lurking in the shadow of Ukraine’s heavily advertised counteroffensive in Kherson, the Kharkiv campaign took Russian forces by surprise. It became a textbook example of a fast-paced breakthrough and exploitation operation – the very sort of campaign Russian armored units mostly failed to achieve at the beginning of the war.
In this article, we’ll look at how Ukraine’s outgunned forces achieved this stunning, little-anticipated victory.
1—Shaping the Battlefield
After a disastrous war-opening assault on Kyiv, the Kremlin in April reshuffled its battered forces and adopted a strategy of massive artillery bombardments to slowly push Kyiv’s forces out of the Donbas region in Ukraine’s east.
The situation looked grim for Ukraine by early July as casualties piled up and Russia gradually captured one pulverized community after another. But that’s when Kyiv began employing newly received HIMARS rocket artillery systems for precision strikes targeting Russian ammunition supplies, headquarters, air defenses, and bridges. At the same time, donations of superior Western artillery systems to Ukraine reached a critical mass, giving Kyiv qualitatively superior firepower that it used to stave off Russia’s larger artillery arm.
Ukraine’s HIMARS onslaught reportedly reduced Russian shelling to one-third of its former level, and it quickly exhausted Russia’s ability to mount major offensive operations. By early August, Russia’s military had switched to a defensive posture, bracing for an expected Ukrainian counteroffensive in Kherson.
2—The Kherson Counteroffensive
As explained in this earlier article, Ukraine had compelling political and strategic reasons to target Kherson. Russian forces there were defending a bridgehead over the Dnieper river, protecting an area it could barely supply due to bridge-busting HIMARS strikes.
Kyiv’s repeated and prominent statements foreshadowing a Kherson counteroffensive weren’t missed by Moscow. Its forces there prepared three layers of fortified defenses (example here) around the key port city. By early August, the Kremlin had redeployed elite Russian units out of Eastern Ukraine and placed them in reserve to counter a Ukrainian attack on either side of the Dnieper river.
Ukraine’s counteroffensive began on Aug. 29 with a flurry of attacks on Russian positions across the breadth of the Kherson frontline. Within a few hours, Russian media mobilized to declare the offensive a failure, claims swallowed by some observers due to the lack of a dramatic breakthrough and to reports of substantial casualties.
In reality, the initial assaults did expose weak points in Russia’s defensive lines. These were later exploited by Ukrainian forces, eventually leading to the capture of Vysokopillya in September, and collapsing the northern edge of Russia’s Kherson perimeter.
3—The Fall of Balakliya
Meanwhile, a second counteroffensive, unannounced by Kyiv, had begun secretly mustering more than 270 miles to the northeast, in Kharkiv oblast, whose namesake is Ukraine’s second-largest city.
Despite continuous bombardment by Russian forces, Kharkiv’s defenders had smashed Russian attempts to seize the city in March. In May, counterattacking Ukrainian troops managed to push Russian forces back to near the border, only to lose much of that progress to Russian counterattacks. Afterward, the sector ceased being a focus of either side’s operations.
Open sources suggest the Ukrainian force massing for the new Kharkiv campaign consisted of the:
– 92nd Mechanized Brigade (BTR-4E fighting vehicles);
– 93rd Mechanized Brigade (BMP fighting vehicles);
– 80th Airborne Brigade (motorized with BTR-80 APCs and Humvees);
– 3rd Reserve Tank Brigade (T-72 tanks).
Russian bloggers noticed the Ukrainian buildup and the preparatory artillery strikes on Sept. 4-5 that included HIMARS rockets. But the potential significance didn’t filter up the chain of command, which left only a light covering force of Luhansk People’s Republic (LPR) infantry. Such separatist forces, their numbers bolstered by forced conscription, were used as cannon fodder during the summer fighting. They suffered from poor morale and lackluster equipment.
At 2 p.m. on Sept. 6, Ukrainian forces converged eastward towards Balakliya, according to a Russian account, spearheaded by a “tank fist” of 15 to 17 tanks supported by special forces. Meanwhile, to the north, the 103rd and 113th Ukrainian Territorial Defense Brigades mounted an attack down the P7 road towards Chkalovsk.
Russian accounts describe Ukrainian tactics thusly: “[T]he advance group with mechanized infantry and special forces operators speeds into the city center, dismounts, suppresses all nearby enemies, then extends control over the settlement.”
The LPR regiment defending outlying villages withdrew abruptly, leaving behind internal security troops – riot police, essentially – to be overrun by the Ukrainian armor.
Russian defenses were unable to cope with the Ukrainian attack. The local reserves that would have counterattacked or carried out hasty delaying actions had been sent to the Kherson region. Ukrainian columns chased Russian logistical, artillery, and air defense support units, which were forced to leave behind valuable equipment.
Russia’s air force tried to intervene by strafing, rocketing, and even gravity-bombing Ukrainian units. But that proved unsustainable: The aircraft struggled to visually distinguish Ukrainian and Russian forces, and Ukraine had massed ground-based air defense in the sector. They promptly downed a Su-25 attack jet (wreck here) and possibly several helicopters, deterring Russian aviation.
Though a man-portable missile downed the Su-25, Ukrainian sources claim radar-directed Gepard armored anti-aircraft guns donated by Germany proved especially effective. Conventional wisdom views this type of weapon as obsolete.
4—Kupyansk, Rail Nexus
By the time Russian forces in Balakliya fled on Sept. 8, Ukrainian forces had already peeled off into southeastern and northeastern combat groups. The latter rolled down the P7 highway towards the offensive’s true prize: Kupyansk, with its bridges over the Oskil River.
#Ukraine: Intense footage of a mixed Foreign/Ukrainian unit in action during a recent Ukrainian offensive, during which a large quantity of US-donated materiel is used; from M1151A1 HMMWV (Humvee) with mounted Browning M2 HMG, to M136A1 AT4-CS AT launchers.pic.twitter.com/uUWInP78Nx
— 🇺🇦 Ukraine Weapons Tracker (@UAWeapons) September 8, 2022
Videos show light Ukrainian forces mounted in armored Humvees tearing into town, heavy machine guns blazing, while infantry dismount. Such “flying columns” would be foolhardy against a well prepared adversary, but they are effective for rapidly seizing ground when the enemy is fleeing and unable to mount a robust defense.
— Veli-Pekka Kivimäki (@vpkivimaki) September 9, 2022
Many emotional moments were recorded as Ukrainian columns advanced through towns that had been under Russian occupation for six months.
People are greeting Ukrainian defenders in liberated Balakliya. One man in this video even stand on his knees. It’s hard to describe emotions. But it’s a beginning. Still a lot people in Ukraine dream to see their town liberated from Russians. pic.twitter.com/N2vxFaZmpg
— Oleksandra Matviichuk (@avalaina) September 8, 2022
Kupyansk’s importance went beyond its bridges. Russia’s ground forces are much more dependent on trains for logistical support than the U.S.’s more expeditionary military. But Russian forces in Kharkiv and near Izyum could only receive supplies via a single railway line, connected to the northern border with Russia, and running through Kupyansk.
AFU 🇺🇦 counter-offensive in Kharkiv region for the last three days 🔥 pic.twitter.com/8Mpj3fVPqB
— Tarmo Juntunen 🇨🇿 🇺🇦 🇪🇺 NAFO (@TarmoJuntunen) September 9, 2022
By Sept. 9, Ukrainian forces had reached western Kupyansk, effectively blocking its usage as a rail junction. A day later, they fully controlled the city.
5—Izyum Pocket, Deflated
Before Kupyansk’s fall, the southern prong of the Kharkiv offensive had curled south toward Izyum, site of a major concentration of Russian forces that was about to lose its primary logistics link.
Izyum-based units had their backs to the east, and the widest part of the Oskil River. Options for supply, retreat, and reinforcement were now constrained to just one road running through the neighboring city of Lyman.
Worse, Ukrainian forces further south also began attacking Izyum and Lyman on Sept. 8, threatening to trap a large Russian force in a pocket.
KHARKIV/ 2300 UTC 9 SEP/ Late reports on 9 SEP indicate that some UKR task units have engaged Russian armor within the city limits of Izium. At present, UKR artillery commands the only road entering or leaving Izium, the 0-211437. This will seal the urban battle space. pic.twitter.com/6PcvR9xaV4
— Chuck Pfarrer | Indications & Warnings | (@ChuckPfarrer) September 9, 2022
Finally on Sept. 10, Russian forces in Izyum chose to avoid a greater disaster by withdrawing. They left huge quantities of equipment behind. Russia’s garrison in Lyman (two Russian military regiments and LPR conscripts) reportedly is barely holding back repeated Ukrainian assaults.
The flight from envelopment led to several chaotic encounters. In one recorded incident, a retreating Russian tank blundered into a column of Ukrainian trucks full of special forces approaching from the opposite direction. It tried to race past them and crashed into a large tree.
In another unusual skirmish captured partially on video, a Ukrainian armored column led by a T-64 mine-roller tank encountered a Russian BMP fighting vehicle on the road. As its machine gun was non-functional, the roller-equipped vehicle rammed the BMP, killing the occupants.
The fall of Izyum may open an eastward corridor for Ukraine to try taking back Lyschansk and Severodonetsk, locations captured at great cost by Russia in June and July.
Ukrainian mechanized forces also made a probe in Pisky, close to Donetsk’s airport, on Sept. 10, but they were repelled.
By Sept. 11, Moscow began broadly withdrawing forces in areas northeast of Kharkiv, even those that hadn’t come under attack, in an apparent measure to shore up untenable defensive lines.
These withdrawals left behind a huge bounty of captured equipment for Ukraine, including dozens of BMP fighting vehicles and upgraded T-72B3 and T-80BVM tanks; multiple 2S3 and 2S19 Msta self-propelled howitzers; towed MT-12 and KS-19 100mm guns; BM21 Grad rocket artillery; BTR-82 and MT-LB APCs; and Tor-M1, Osa, Shilka, and Tunguska short-range air defense vehicles.
The silver lining for Moscow is that its force’s rapid flight denied Ukraine the chance to encircle larger Russian formations and destroy or capture them. However, routed units will still take time to restore into fighting shape. They have lost vehicles, fuel, and ammunition, and morale has collapsed.
The main question now is whether Ukrainian forces will continue riding the eastward momentum of the Kharkiv breakthrough, and how far they can go before the exhaustion of troops and supplies takes hold. The other question is how long it will be before Russia scrapes together a force that can delay the Ukrainian troops and build a more robust defensive line.
By Sept. 12, preliminary reports suggested that Ukrainian forces issuing from Kupyansk were closing in on Svatove, a key logistical node. If secured, from there they could roll south into Rubizhne and Severodonetsk, forming a pincer with Ukrainian troops advancing eastward. They could reverse one of the few politically important successes of Russia’s summer offensive.
The key supply junction of Starobilsk, east of Svatove, also appears vulnerable, and it may have already been evacuated by Russian forces. Should such dominoes keep falling, Russia’s puppet “republic” of Luhansk could lose most of its territory.
However, some analysts, and even Ukraine’s defense minister, suggest Ukrainian forces might not advance far east of Kupyansk and the Oskil and Siverski Donets Rivers. They might prefer to avoid overextension, consolidate their positions around defensible rivers, and ultimately shift forces to other critical sectors.
Deep advances into enemy territory sometimes expose an attacker’s flanks and exhaust combat readiness, a vulnerability German General Erich von Manstein exploited against overextended Soviet forces in the 1943 Battle of Kharkiv.
That said, Russia currently seems to lack enough reserves to execute a strong counterthrust. Already, elements of the newly formed 3rd Army Corps and 90th Guards Tank Division (badly mauled in March attacking Brovary) were flung hastily into Kharkiv to little apparent effect.
The other big question is whether defeat in Kharkiv will have aftershocks in the more strategically critical Southern Ukraine. Especially important is Kherson, where Kyiv’s counteroffensive continues to chip away, resulting in Russia’s northernmost forces falling back several miles on Sept. 11.
Given Ukraine’s success in quietly massing forces near Kharkiv, there are indications Kyiv may have even more fresh forces ready to attack elsewhere. If it does, that could herald further setbacks for Moscow.
As Kyiv secures Kharkiv, it might also redeploy elite units there to other sectors. Ukraine has already demonstrated its ability to quickly and discreetly shift brigades between fronts, thanks to its shorter and more secure interior lines of communication.
What’s exterior/interior lines?
This map shows the difference between RU and UKR’s lines of supply and support.
A quick glance shows how long it would take to get from one end to another for RU supplies, and how UKR can move more quickly inside their lines 11/ pic.twitter.com/ncErUW2Kt0
— Mark Hertling (@MarkHertling) March 18, 2022
Given Ukraine’s extraordinary battle of maneuver in Kharkiv, Kyiv has now proven it can execute a successful, large-scale combined arms offensive to liberate occupied territory. It has also shown that Russian forces are not some unstoppable juggernaut with inexhaustible reserves of troops and ammunition. This will stiffen Western support for Ukraine, and it is already souring domestic support in Russia for Putin’s invasion.
There will be much more fighting this fall before winter weather slows down the pace of operations. In the coming weeks, Ukrainian forces will seek to sustain or repeat their feat of arms in Kharkiv, while Russia will scramble to firm up new defensive lines and hold onto territory it seized in 2022 — and possibly even in 2014-2015.
Expert Biography: Sébastien Roblin writes on the technical, historical and political aspects of international security and conflict for publications including The National Interest, NBC News, Forbes.com, War is Boring and 19FortyFive, where he is Defense-in-Depth editor. He holds a Master’s degree from Georgetown University and served with the Peace Corps in China. You can follow his articles on Twitter.