President Vladimir Putin attended a military parade and gala concert in Volgograd (formerly known as Stalingrad) on Saturday, where Soviet troops fought the Germans for 200 days. The battle ended in Feb. 2, 1943.
On Friday, Putin hosted a reception at the Kremlin to honour nearly 200 veterans of the Second World War.
"We have to do everything so the memory of the Battle of Stalingrad, the truth about it, will never fade away," he said. "From this point – from the unbowed city – our forces began their march to Berlin."
"This was a very important battle. The whole world remembers this battle of Stalingrad," said Anatoly Kozlov, a Soviet lieutenant in the 158th armoured division.
"Of course we were afraid. But as soon as the fight started, it was gone. During the battle, it was kill or be killed," he said. "That’s why I tried to kill and tried to survive. It was the same for every soldier. …Nazis thought they had already won. Because for one year we retreated. We left a lot of ground. And it was possible to think like this."
Kozlov did not believe he would survive the battle and wanted to say good-bye to his mother, but she lived in a German-held territory.
Then he said the momentum shifted, partly because Stalin issued an order that no Soviet soldier could defect or turn around.
"This order: not one step behind played an important role. … We stopped the Nazis. We needed that victory," Kozlov said.
Germans are also marking the anniversary, although in a much quieter way.
The Bundeswehr Military History Museum in Dresden has a special exhibition aimed at dispelling some of the myths around the battle, curator Jens Wehner said.
Many of the weapons, clothing, letters and other artifacts are from Russia and have never been seen in Germany.
"[Most people] think it’s the most decisive battle, which is actually wrong. There were more bloody battles on the Eastern Front in 1944-45 but the propaganda in 1942 and 1943 was much higher than in the later years of the war. … We want to show how this myth was created," he said.
Destroying Stalingrad was not meant to be a major military operation, he said. It was almost an afterthought of the German army, on its way to the oil fields in the Caucasus.
"The … biggest mistake of the German army was to underestimate the Soviet army. …Because they were Nazis, they think that Russians are untermenschen [sub-human] and they had not the abilities to plan such complicated operations," Wehner said.
That miscalculation cost more than one million lives on both sides, as the battle raged from street to street, building to building. Of the 200,000 German soldiers, only 5,000 survived.
Still, both sides seized on this battle as a symbol, Wehner said.
The Nazis used it as a rallying cry. The Soviet Union and Allies touted it as a decisive victory against the Nazi war machine.
It was also one of the first times the mass media on both sides of the Atlantic had such a strong influence on the public.
"There you can see British newsreels and American newsreels using Soviet pictures from 1942 showing the British and American population about the Battle of Stalingrad and the victory of the Soviet forces," he said. "The media response was like this British newspaper (with the headline): Huns Collapse at Stalingrad."
Most historians believe this was a crucial battle, said Arnd Bauerkaemper, a professor of modern history at the Free University in Berlin.
But he argues that the United States joining the war and the defeat of German troops in Africa, all of which happened around the same time as the Battle of Stalingrad, were the decisive combination.
"These two battles were certainly a turning point, not only in military terms but also in psychological terms," Bauerkaemper said.
"The Germans did know this was a profound and very severe defeat. Many Germans lost confidence and the Nazi rulers sensed this. It's by no means a coincidence that Goebbels, the propaganda minister, staged a huge rally in Berlin in February 1943, a few weeks after [the] defeat of Stalingrad, and he tried to commit Germans to total war, in order to combine all efforts, mobilize all resources in order to still win this war."
Germany fought on for two more years after Stalingrad, until they were totally defeated.
Seventy years later, there are some moves towards reconciliation between the few remaining survivors of the battle. It is part of the official ceremonies in Russia this weekend.
But in Germany, the focus is on education, said Major Sebastian Bangert, spokesman of the Bundeswehr Military History Museum.
"As far as I know, this is the first time a museum in Europe has showed the battle from this perspective. We just want to deal with the myth. That Stalingrad was a cruel battle, that is not the question, but it was one of thousands of cruel battles and not as important as people believe," Bangert said.
"For us as a history museum, it’s important to be very close to the sources. We show the Battle of Stalingrad, we offer different perspectives and the visitor has to choose a perspective. He has to think himself."