Kingdom of Novgorod
Population of 45 million
Capital is Novgorod
Constitutional Monarchy
After victory over the Swedes at the Neva in 1240, and over the Livonians at Lake Peipus in 1242, the young Prince of Novgorod, Alexander Nevsky, was elected king. This was unprecedented in Novgorod's history, but proved to be a wise decision. (This POD is very early, so it doesn't really fit into 'After 1900,' but I liked the idea. I might make a separate TL later). Under his aggressive leadership southern Finland was taken, and Sweden was reduced in power thanks to his alliance with Norway. Estonia was captured shortly before his death in 1263. His son Vasily inherited the throne of Novgorod.
Novgorod superseded Muscovy due to its significantly better trade links, and the region was annexed peacefully in the 1350s. The Muslim Khanate of the Golden Horde remained a reasonably friendly neighbour to the south-east. For the next 200 years Novgorod was largely peaceful, although expansion north-eastwards continued slowly. The monarchy was strong, but not too oppressive and the Wars of Religion after the Reformation had no damaging effects due to the reasonable freedom and loyalty of the country's citizens, most of whom remained Orthodox. However in 1585 Poland-Lithuania, which had grown significantly at the expense of the minor rulers in the Ukraine, invaded Novgorod. The resulting war was initially devastating, but a loose coalition of Novgorod, Brandenburg, Sweden and Polovtsy finally destroyed most of the invading force north of Kiev in 1588. Kiev-Polovtsy, later becoming simply Ukraine, became the major power in southern Russia, while Novgorod made its first gains in the west since the 1200s. Poland-Lithuania survived, expanding into Latvia and destroying the final remnants of the Livonian Order.
Meanwhile the King's Arctic Exploration Company was founded in 1678 by Alexander IV. One of its most famous members, Vitus Bering, went on to discover and chart the Bering Strait in 1728. Novgorod recognised the economic potential of links with North America, and the first permanent trading post was set up in 1739. Alaska officially became an overseas territory of Novgorod in 1770. Novgorod took part in the Seven Year's War (1756-63) alongside its allies, Britain and Brandenburg, against France, Austria and Spain. Novgorod secured Alaska, and gained Hawaii and modern day Washington and Oregon, but these two later rebelled and became independent in 1816. In Europe its armies marched through Ukraine (friendly but neutral) and attacked eastern Austria.
Despite its actions being successful, victory had unintended consequences for Novgorod. Austria collapsed in 1770, with German speaking territories being annexed by Brandenburg, Hungary becoming independent, and Ottoman gains in the south. Novgorod was left vulnerable with many potential enemies. The Ottomans frequently raided its ally Ukraine, and minor conflicts continued for almost a century. The American War of Independence also involved Novgorod, which intervened in order to maintain good relations with Britain. The colonists were still successful, but a conference at the end of the war divided the rest of the continent between Britain, Novgorod and Spain. A central buffer zone was left to the Native Americans.
In 1789 the French revolution took place, but would lead to Napoleon's defeat and exile in 1814. Novgorod refused to join the Continental System and stop trading with Britain, but the French invasion of 1812 was a disaster, most of the force dying during the retreat, after the Battle of Pskov, not far from Novgorod City itself. However, Novgorod did not take part in the fight to liberate central Europe in 1813-14, fearing that a decisive victory for the Coalition would make Brandenburg the dominant power, with its pan-Germanic ambitions. This created lasting resentment in Berlin.
Brandenburg's aggression led to the successful invasion of Poland in 1839, and much of Poland's territory was lost. The Franco-Brandenburg War of 1859 resulted in a short occupation of Paris by Brandenburger troops, and increased influence in newly unified Italy. The following year a German nation was formally founded, and the other Great Powers began to form secret alliances. In 1864 Germany attacked Denmark to capture Schleswig-Holstein. Novgorod activated its old alliance with Denmark-Norway, and the First World War began. By 1865 it pitted Germany, Italy, Hungary and the Ottoman Empire against Novgorod, Ukraine, Britain, France, Denmark-Norway and Poland. Iberia, Sweden, Switzerland, Benelux and the Balkans stayed neutral