God Bless The Tsar!
The POD operates around the assumptions that Tsar Alexander II of Russia narrowly avoided an 1881 assassination attempt (in reality he was killed and Russia's next Tsar set Russia on the path to revolution) by "The People's Will" terror group. Alexander saw the sparing of his life as a sign from God that he had much yet to do, and so he set about with reforms that, despite alienating much of the aristocracy, won over much of the lower- and middle-classes, heading off revolutionary groups and their teachings and making Russia into a Great Power and a Tsarist nation through to the present day. Other PODs include Russian enforcement of the Treaty of San Stefano in 1878, leading to the creation of a Bulgarian kingdom and increase in Russian prestige, and the survival of Alexander's first son Nicholas in the 1860s through a period of tuberculosis (again, he died in this).
Prior to the ascension of Alexander, Russia was a backwards, reatively uncivilised country, with a slave-owning society and small industrial base. After the failed assassination attempt, Alexander II decided that he had been 'spared by the Lord, that I might continue to do his work in this Empire.' No matter what the aristocracy thought, he pressed ahead with the Twenty Year Plan. Among other things carried out were: significant land reform that saw former serfs (emancipated in 1861) able to claim a grant of land that their family had lived on for more than four generations. Also instituted were educational reforms (boys only, of course), which saw the major centres, and then gradually the rural areas, have full access to education, if not education of the quality seen in Western countries like Britain and Germany.
In 1895, the programme of industrialisation developed in the 1870s had come to fruition. Russia now had industrial turnout comparable to Italy or Belgium, and the Duma gave even the common man something of a voice--though Members could only be male landholders with an income of at least 100,000 rubles per annum. Further progress in government was hindered by Alexander's retention of autocratic powers, a move he saw as necessary to prevent backsliding.
A significant social development was averted as the wave of pogroms against Jews (which in OTL occurred due to the assassination) did not occur, and although the Jews remained a persecuted minority, they were somewhat better off by the 1890s - even if new Jewish settlement east of the Dnieper was forbidden. Elsewhere in society, the aristocracy retained their position as the most powerful nobility in Europe (albeit weaker then previously), middle-class up-and-comers like Vladimir Ulyanov represented the growth of Russia's economy, and the lower classes saw increases in real standards of living thanks to land reforms, cancellation of serf debt and labour laws inspired by those in the UK. In Poland and Finland, the locals had been encouraged (or "encouraged") to develop along Russian lines (though Poland was host to a large Russian military presence due to German-Austrian proximity), and relations were livable, if they failed to be loving.
Foreign relations were dominated by Asia and the Balkans; in both areas Russian expansionism frightened the other European powers, especially following Russia's victory over Turkey in the Russo-Turkish War of 1877 and the creation of Russian satellite states in Rumania and Bulgaria. However, following the defection of Russia's supposed 'little brothers in the Balkans' to ally with Serbia in the short-lived Balkan Pact, the Empire's focus was on seizing what it could of the decaying Chinese Empire, and it was moves towards Mongolia and Manchuria that brought conflict with the nascent Empire of Japan.
During the 1890s, the Russians had focused on increasing their economic activity and industrial output. A part of the 20-Year Plan was the development of the Siberian wastes. Vladivostok was now the sixth-largest port in Russia, and the colony at Port Arthur in China was almost as large (as an ice-free backup for harsh winters). This had meant that the Russian influence in Manchuria was now almost enough to worry the other Great Powers - especially Japan. From 1901 to 1904, Tokyo made repeated requests for negotiations regarding the situation - Russia refused, and to defend her possessions Japan declared war.
On October 4, 1904, Imperial Japanese Navy ships blockaded Vladivostok, Port Arthur, and bombarded Magadan. Troops swarmed from Korea to attack the rail links to the great ports, and Russia, confident of no intervention by anyone else, declared war on Japan. The war went poorly for Russia at first, as no reinforcements could be shipped any sooner than within two months, and winter was approaching. However, the garrisons at the ports were well-stocked, and the Siege of Port Arthur was broken by April 1905, at a cost of 125,000 Russian to 93,000 Japanese casualties. With the problems in trade starting to hit US markets, American President Theodore Roosevelt intervened. The Treaty of Portsmouth was signed between Russia and Japan on August 22, 1905, with Russia ceding authority of Port Arthur, and Japan guaranteeing to keep clear of any actions threatening to Russia's presence in northern Manchuria.
Russia remained rather neutral up to the Russo-Japanese War, with Alexander II distrustful of the French and British and Austria equally thanks to his memory of the Crimean War, and his son Nicholas even more paranoid. However, seeing that they would be screwed to the wall without allies, Russia signed friendship treaties with Serbia, Britain, Italy and the United States, the last of those being in October 1905, after the Portsmouth Treaty.
The Great War
In 1914, Franz Ferdinand was killed by a Serb terrorist group in Sarajevo, Austro-Hungary. That empire soon demanded concessions from Serbia. Serbia asked Russia for aid, and Nicholas, after receiving a vote of support in the Chamber of Deputies and House of Commons, began to apply pressure to Austria. Then Germany intervened, France began mobilisation, and the war Europe had dreaded began. Initially, Russia kept out of the war, but maintained enough of a military presence in Poland to keep a significant portion of the German army in the east while they attacked France--the Russians realising that if Germany were free from an enemy in the west, Byelorussia and the Ukraine would be eyed up by the Kaiser. As it was, the Russian Army was clearly not up to modern standards. While there was enough in the way of supplies, it was reckoned that it would be better to wait until the Germans decided that Russia had made the choice to stay out, and when the German armies there were removed to France, a surprise attack could be made. In December 1914, the Germans did start to move, and by March 1915, a Polish-led force (as the attack was being staged from Poland) struck out for Konigsberg. The attack reached the city, but timely reinforcement saw the end of the Allied hopes for a quick war. The war see-sawed, with Poland falling to the Germans in 1916-17 before a solid defence was established and stalemate ensued, characterised by mobile warfare across vast distances. The Germans proved content to hold what they had, and moved back to France, until American troops landed in 1918, rolling the Germans back and forcing an armistice on September 9, at 9:09 am.
In 1919 Russia granted full independence to Poland, Finland and the Baltic states (Small nationalist risings occurred in Belarussia and the Ukraine, but these were crushed) and settled down to a prosperous post-war. In Germany, the rumblings of depression and the National Socialists were largely ignored, as focus resumed on industrialisation and development. The good cheer was stalled when Nicholas II died in 1921, but his successor, Peter IV, managed to charm the people with his wit and charisma.
The Depression was unkind to Russia, though. Faulty credit and lending practices saw fortunes lost in days, hours, seconds. From a peak in 1928, Russian industrial output fell to a third of those levels by 1931. Then, in the triennial Duma elections, Joseph Dzugashvili, who went by the name of Stalin, was swept into power under suspicious circumstances as Prime Minister of All the Russias and Lieutenant-Commander of the Armed Forces. He ruled almost as if there was no Tsar, learning from Mussolini in Italy. The first Five-Year Plan came into effect soon afterwards, with dams being built on the Volga and Dnieper, and factories springing up from Kiev to Khabarovsk. The Tsar was not displeased: indeed Peter approved of a strong frontman to stand up to the German menace brooding across from Poland.
In 1936 Stalin sent volunteer brigades to Spain to aid the Spanish Republic in its civil war. Hitler did the same, but aided the opposite side. The German-supported Nationalists won, and Russia's command panicked. The new fear of German attack, reinforced with the occupation of Czechoslovakia, led to a defensive attitude that allowed Germany to annex most or all of Poland in 1939. The UK and France declared war, but Russia did not. Peter and Stalin knew that Hitler was too strong for Russia's army, downgraded during the Depression. Fear of the Germans' superiority skyrocketed with the defeats of Poland, the Low Countries and France in quick succession. And then, despite having peaceful intentions towards Germany, Russia was invaded on June 11, St Barnabas' Day, in Operation Barbarossa.
The Great Patriotic War
The Germans had the advantage of surprise, further compounded by the fact that a stalemate within the Russian Imperial High Command (Stavka) meant the Russian Army was in limbo between preparedness for attack and defence. As such, the Germans made rapid progress, taking Minsk by the 16th of the month, Lvov by the 20th, and msent the Russians into seemingly hopelss confusion. Seeing Stalin's shocked indecision, Tsar Peter assigned General Tukhachevsky to repel, or at least delay, the Germans until reinforcements could be summoned. The First Retaliatory Offensive, codenamed Operation Tannenberg, was at best a mild failure (30 divisions being encircled by a German flanking strike in the Pripet) with one bright(ish) spot in the Battle of the Brody Triangle, where Russian tankists inflicted heavy losses on the German First Panzers. They were defeated nonetheless, and were forced to retreat to the pre-prepared "Tukhachevsky Line" which extended from Smolensk to Kiev to Melitopol. This followed the time-held tradition of trading land for time to rearm and repel.
However, as had occured with the French Maginot Line, the Tukhachevsky Line was also outflanked. This happened thanks to a German thrust through the neutral but pro-German Baltic states. In response, the Russians marched into Estonia to 'protect the population' from the Nazis, a clumsy move that only inflamed the Balts against their former Imperial overlords and fanned naitonalist resistance. By harnessing this Germany's Army Group North was able to reach Petrograd by July 21st and encircle and besiege the city by August 5th: Russia's government evacuated to Kazan although Stalin, having regained his confidence by seeing the failure of Peter's commanders, moved to Moscow, the 'spiritual home of Holy Russia'.
From then until 1943 the fate of Russia hung in the balance, with things bleakest in December 1941 as German armies lay siege to Petrograd, threatened Moscow and spilled into the Ukrainian steppes. This was followed by regaining of northern territories in 1942 (Finnish neutrality was vital in maintaining the security of Lend-Lease convoys, and Finnish Karelia gave a roundabout supply line for Petrograd) and the German thrust into the south, culminating in the apocalyptic Battle of Tsaritsyn (renamed Stalingrad in honour of the Premier after victory). This was the tipping point, and with the Axis forces deflated the long hard rollback to the border began. By August 1944 the last of Russian soil was cleared (after the bitter battles of Kursk, Kharkiv, Rostov and the Crimea), and an invasion of Japanese client state Manchuria was mounted...sot of successfully. By early 1945, the Nazis were defeated, with Tsarist tanks in Berlin and the Dresden Conference delineating spheres of influence.
The after effects of the war were a devastating blow to the Russian Empire anyway, erasing the best of a generation of two: 25 million dead was the most reasonable figure, and this hideous toll led to the Russian postwar policy of revenge upon their invaders and reconstruction of their ruined Empire. This was aided in the short term by seizing a third of Occupied Germany's industry, and fueled in the long term by roping the East European states into trade agreements that ensured the Russians could keep their economy going--and, perhaps more to the point, their military well-armed.
The Russians were pitied and feared in equal measure by the Western Allies: yes, the Russians had suffered hideous punishment from the Germans and deserved compensation, but on the other hand, hadn't WWII only proved that a harsh peace didn't keep the Germans down? This cut no ice with the Empire, who wasted no time in imposing satellite governments in Eastern Europe, most notably the (East German) Prussian Republic, Hungary, the resurrected Czechoslovak state, and the well-cowed Balkan kingdoms. The Russian rein was tightened even more after Yugoslavia's monarchy was toppled by a popular revolution led by Josip Tito's Communists and a socialist government was introduced.