It was perhaps badly-timed to get the world's media attention (due to a royal death sucking up all the media oxygen... which it continues to do...), but nevertheless the Ukrainian military just had a stunningly good week.

In one sector of their country, they achieved what can only be called blitzkrieg -- "lightning war." Their forces set out from Kharkiv and within days held not only Kupiansk and Izyum, but all Ukrainian territory -- right up to the Russian border -- which is west of the Oskil River. The BBC has an update on just how stunning a development this truly is:

Ukrainian troops have inflicted a "major operational defeat" on Russian forces, according to the Institute for the Study of War (ISW).

Russia confirmed it had withdrawn from the key towns of Izyum and Kupiansk on Saturday, saying that the retreat would allow its troops to "regroup."

Both towns were major logistical hubs for Russian forces in Donbas. Russian troops had been trying to advance towards Kramatorsk and Slovyansk.

Izyum in particular was one of the most fortified sections of the Russian front line.

Ukraine said it had retaken more than 3,000 sq km (1,158 sq miles) from Russian forces.

Justin Bronk of the Royal United Services Institute (RUSI) told the BBC that Russian positions in Kharkiv had suffered a "total collapse."

The Russian withdrawal was, he said, "certainly the most dramatic reverse that we've seen from the Russians since they retreated from Kyiv in April."

The ISW said Ukraine now controls almost all of the Kharkiv region and the advance had ended the prospect that Russia could capture the whole of Donbas in the current stage of the war.

Previously, Russian officials had said their forces were fighting for the "complete liberation" of the Donbas, which broadly refers to Ukraine's eastern regions of Donetsk and Luhansk, where Russian-backed separatists held significant territory before the invasion.

[That article includes some excellent maps, by the way. Or you can go to an interactive site with a current map that you can zoom in on.]

This is all part of the first major land war Europe has seen since World War II, and the basic tactics are the same as they were back then, really. First, soften up your enemy with false information -- the Ukrainians let it be known they were reinforcing their forces in the south and would soon be launching a major counteroffensive. This wasn't a complete feint, but it was to a large extent. The Ukrainian forces in the south have indeed launched their own simultaneous counteroffensive and are inching towards Kherson and all the land west of the Dnieper River, and so far they have had some success -- just not as dramatic success as was seen in the north, where their forces quickly overran the Russian lines.

Which brings us to the second step: attack the enemy's supply lines to weaken the forces at the front, and then quickly stage a breakthrough so you are fighting behind the entrenched front lines the enemy has set up. The Ukrainians did this by cutting off Izyum -- a fortified part of the Russian line -- which meant no food, no fuel, and no ammunition for the Russian forces. Then with a quick push, they made it through the entrenchments further out and started taking large swaths of the countryside. The Russians could see that Izyum might get completely encircled and cut off, so they just bugged out. They retreated across the Oskil, leaving a whole lot of their tanks and ammo and other equipment behind. It was a total rout. This was not a well-planned retreat, folks. It happened in days -- in a matter of hours on the most successful day for the Ukrainians, in fact.

Throughout it all, the Ukrainians have apparently been successfully using psychological warfare as well. They've been sending letters to the occupied areas and broadcasting on the radio entreaties for the Russians to surrender -- with information on how they should do so, how well they will be treated, etc. This seems to have undermined morale, even in the south (where the Russian soldiers know by now what a major defeat the Red Army just suffered in the north).

Morale is important, ask anyone who has fought in a war. The Russian soldiers largely have no clue why they are fighting. They have been lied to -- first they were told they were fighting "Nazis" in Ukraine, and then apparently (from recently-captured Russian prisoners of war) they were told they were fighting "America." But the Russian media underground has been getting the message back to the Russian people what an absolute fiasco this whole war has been from the very start. Also, a whole lot of parents of soldiers have had body bags come home, which adds a cumulative effect to the population figuring out they've been lied to.

This saps the army's morale. So do large defeats on the battlefield.

The Ukrainians, on the other hand, all know what they are fighting for. They know it full well, they don't have to be told. They are fighting for their homeland. They are fighting an invasion. They want their country back. Their morale -- aided by all these battlefield victories -- is sky-high.

And that can make all the difference, in the end.

Vladimir Putin is now actually getting political pressure back at home in Moscow. He's getting pushback from a number of different directions, which is surprising in Putin's Russia, since it usually just does not happen. He appears weak, which is fatal for any strongman.

Of course, this is just one gloriously victorious week for Ukraine. Look at those maps -- they've still got a long way to go to actually reclaim all of their country. But if they keep winning, that is going to become more and more of a realistically-plausible goal.

Nobody knows what the next stage of the war will look like. Perhaps the Russians will pull back even further both in the north and the south. They are facing a decision whether to split their forces and try to fight a two-front war or just strongly reinforce one area at the expense of the other.

Things could always turn around, or (more likely) bog down. The Russians may pull back to a smaller area of captured territory; an area that they actually have adequate forces to successfully defend. Anything could happen, they could even regain the offensive momentum somehow.

But at this point, it seems at least an equal probability that the Ukrainians will build on their success and their newfound blitzkrieg tactics and start taking back even more of their country.

No matter what winds up happening, though, the Ukrainian military forces just had a heck of a good week (no matter what royal personage happens to be awaiting burial right now).

-- Chris Weigant

Follow Chris on Twitter: @ChrisWeigant