Ever since their victory in Second Sino-Japanese War and transformation of China into giant client state, the Japanese ambitions only grew more and remained a major threat to Russian strategic plans. Island corporations invested heavily to further industrialization of Korea and Manchuria, using cheap Chinese labour force and tried to forge a Pan-Asian alliance with Ali Khan's India, rather than rejoin the Entente, which deemed the regime just as same undemocratic as Russia - secret negotiations were on the way, however, to at least stop further Renewalist conquests through Non-aggression and Defensie Pacts. Joined Entente and Co-Prosperity Sphere's forces had a chance to do that.
Just as the Berlin, there were Russian soldiers in Paris, Rome or London. Complete and utter destruction of the Internationale and nuclear bombardment of it's last country member showed the Russian determination to never allow any European country to be a threat. But there was still one enemy, which actually still occupied the lands of the old Empire and prepared millions of soldiers to fight them. And not only them.
The Empire of Japan's Army managed to recover from devastating losses from the war with China and pursued development of weapons able to destroy any enemy superior in numbers of soldiers, training or equipment. This was not something Russia could tolerate any longer and while Russian aristocratic warlords utilised their conquests in Europe, the bulk of imperial forces were sent to the Far East.
Expecting the right kind of Japanese reaction to such a move, soldiers sent against their now restless client state encountered heavy resistance led by the most vigorous collaborationists - the kind which could expect absolutely none leniency after the reconquest of the country and it's quick reincorporation into the Russian Empire.
There was only one option for the Japanese to react and their only hope was the support of the Entente or Ali Khan's Empire: neither were interested to help, as the Russian advance soon made several countries dissapear from face of the Earth and Japanese themselves had to soon evacuate it's soldiers and civilians from Korea and China.
The Japanese counted on Russian strategic inability to effectively supply massive armies in such difficult terrain, but underestimated the amount of development in Siberia and Mongolia in the passed decade: additional Trans-Mongolian and Baikal-Amur Railways combined with increased number of roads and military bases made massive invasion possible despite the gruesome Siberian winter conditions. Entire divisions clothed in fur coats marched along with slowly advancing tanks and trucks with permanently hot engines.
Further south, soldiers encountered better weather conditions, but these largely undeveloped areas with virtually none reliable roads had to rely on the infantry and the heaviest weapons were the ones carried by donkeys or several soldiers carrying parts of cannon or howitzer. These soldiers were mostly Georgians, Armenians and Finns who fought in most challenging areas without roads for centuries.
To prevent Japanese mobilized reinforcements on the Home Islands to join the battles on the continent, and to cut off the head of a snake, it was decided by the Tsar to cut off the head of a snake: their Emperor survived the atomic bombardment in his bunker, but losses and the destruction of capital city without ability to even avenge such loss similarly, it had desired effects in the end.
In Manchuria, two armies of experienced soldiers with modern equipment fought each other - the ones with superior firepower and larger concentration of troops gained upper hand quickly, but not at the entirely cheap price, not even from Japanese "allies" - in fact, Russians fought Chinese in greater numbers than their Japanese masters and their resistance made a good impression. No longer iliterate rabble fighting Mausers with spears, from times of Boxer Rebellion.
First phase of the war consisted of engaging enemy on each part of front and it's disintegration into smaller isolated part, easy to quickly squeeze and destroy through infantry and armoured charges supported by heavy artillery support, whenever enemy's defenses proved too solid to simply roll over them.
The Japanese prisoners of war in Central Asia, 1950s. Few hundred thousands of Japanese were not released until 1959, working in fields or mines operated by aristocrats and companies in which imperial officers had very profitable shares. Civilian, private contractors also profited from such activities, bluntly using term 'foreign serfs'.
In only three weeks, the frontlines crumbled into smaller pieces as designed in war plan: Xuantong Emperor's Empire-in-exile was used too, calling loyal Chinese to fight collaborationist traitors of the Republic and it's Japanese slave masters and soon, many regiments defected or started to fight as guerilla armies, until Russians arrived.
In one month, Co-prosperity Sphere's fate was decided, as the Russian armies continued in breakthrough operations deeps inside enemy territory. It was around this time too, when soldiers received orders to start dismantle factories and other industrial equipment, which can be used in Siberia or Mongolia.
The Transamur, as it was expected, fell as the first country: after carnage in Manchuria and nuclear strike against Tokyo, military coup done quick work with pro-Japanese officers and officials and swore loyalty to Peter IV. Most of them couldn't hope for star career, ending up as military prison administrators or commanders of most frozen and obscure bases in Siberia, but this a small price, as many traitors paid with their lives and nothing was certain these days.
Imperial soldiers marching in recently recaptured city of Vladivostok. The city itself saw significant development during last 20 years: shipyards and factories were built and military bases had to accomodate the much greater numbers of soldiers, same as the largest battleships, as the Japanese expected to use it as another major port to supply it's armies and it's Manchurian puppet, not just Transamur.
To prevent naval bombardment of city due to lack of Russian Pacific Fleet, which existed just on paper, bomber units and heavy artillery was brought here, with addition of submarine wolf packs, sinking one Japanese transport after another, in areas stretching from Yellow Sea to Kuril Islands.
The Manchurian military surrendered just few days afterwards, as it's main forces were surrounded and both Chinese soldiers and officers were no longer interested to fight a meaningless battles for Japanese, without literally any hope of victory or survival - when Russian officers promised individual units no mercy, when they won't capitulate in one hour, for example, they always kept their word to the letter.
Manchuria itself was used to Russians and their presence over the century, which was perhaps behind the reason of surprisingly easy process to add their land into list of Russian Empire's governorates in years to come.
This action was never approved by the once again reconstructed Qing Empire, which will receive sort of compensation by hanlding them over rest of China: Yunnan warlord state, the last remnant of fallen Sun's First Republic, Tibet, Huijang puppet state and Legation Cities, all were given under the rule of returned Xuantong Emperor. The Tsar of All the Russias preferred the vision of future China as the most loyal, stable, reactionary and important ally, but nothing is without it's price.
First Russian train reaching Dalnyi, known once as the Port Arthur or as the Japanese port of Dairen: now designed to serve the Russian warships and merchants.
In two months since the start of hostilities, China was mostly cleared from Japanese troops, paratroopers and marines took control of Hanoi and Saigon and Russian tanks entering Korea intended to stop only at port of Pusan.
Remaining republican forces only tried to escape into Yunnan, but not all of them succeeded, before collapse of organized resistance.
After three months, the Japanese had no other option but ask for armistice, with over 150 divisions destroyed in battle, surrendered or devastated by nuclear strikes and with dozens upon dozens Russian submarines waiting for more targets around each Japanese island.
Someone had to be blamed for worst defeat in Japanese history since Toyotomi invasions of Korea in 16th century: in that regard, reaction was very much similar - isolationism in foreign policies and military regime resembling old Shogunate, as the Emperor was now under 'eternal protection' by the Navy - as the Army was largely disgraced for the defeat as the main culprit, with many soldiers evacuated from the continent treated as traitors to the nation and the Emperor. There was no request from this government about captured Japanese soldiers for years and no captured officer was ever allowed again to return.
And just in similar fashion as the old Ming Empire previously, Russians supported now re-established state of Korea, which will certainly help keeping Japan in it's place.
