Description
"Polished" version of my first Commonwealth survival scenario.
timeline beep boop
CW = Commonwealth
Basically, the Commonwealth manages to retain its independence through a better effectiveness during wars and in treaties during the 17th Century.
Scandinavia exchanging its Pomeranian possessions for military support could have let Prussia join Sweden and CW's side, instead of Russia's, in the Great Northern War (1700-1721). (IOTL that war kickstarted the decline of the CW, leading to its partition in 1795)
A better enforced victory in that war could've butterflied the CW's survival to this day. Gaining momentum, future treaties, more on CW's favour, could have just let Russia stay away from Polish-Lithuanian [and Scandinavian] affairs.
In the meantime, with a stronger mainland, the colonies on the Gambia river (Saint Andrew) and in the Caribbean (New Courland) are kept and don't get invaded/evacuated by other powers like OTL.
There comes Napoleon. Without a Polish nation to "free" from Russia as OTL, Napoleon just tries to marry his way to the Polish throne, like he did with his brother Giuseppe in Naples and Spain. Meeting opposition from the Polish people, the campaign of Russia will include an invasion of the CW and the creation of the Duchy of Warsaw (analogue of OTL).
After all that Napoleonic mess, the Congress of Vienna (1815) puts things back in order, and the CW is back to its 1800 borders.
In 1848 there was a real proposal to recreate the Polish nation, starting from Posen, in OTL, surprisingly by Prussia, albeit through its new liberal government. It was stopped by an uprising of the Posen Germans. ITTL the proposal is to give back to the CW the Duchy of Posen. Again, a public uprising halts the project.
It's WW1: the war goes as OTL for the most, the CW puts up a strong defense against Germany's Ober Ost plan, and the German war machine stagnates along the coast. Germany and Russia are separated by the free city of Riga, a safe port to bring Entente supplies and soldiers. The bolsheviks can't manage to keep power during the Russian civil war, and the Russian Republic is established. The minimap on 1916 displays the German and Russian presence on CW territory.
The Treaty of Versailles of 1919 makes Germany cede a long-lost Polish territory: its access to the Baltic Sea. This divides Germany in two, with East Prussia left as an exclave as OTL. This and the many other post-war reparations and conditions pave the way to the rise of German revanchism and Nazism as in OTL.
Nazi Germany invades the CW in 1939, WW2 starts as in OTL. Without the USSR, Germany meets no resistance au pair with its military power, putting all of the CW under Nazi control by 1941. Persecution of the Polish/Lithuanian/Ruthenian/Yiddish peoples and the Holocaust happen, just as OTL. The tide turns in 1944, with a succesful attack at Wolf's Lair, which kills Hitler. In the power vacuum, chaos ensures within the Nazi leadership and the CW manages to recover and push back Germany with Allied assistance.
In the post war treaties, the CW will get East Prussia, and cede the easternmost section of Lithuania to Russia, as a compensation for its support during the conflict.
Germany gets divided according to the Western Allies into a northern Germany and a southern greater Bavaria. Bohemia gets Silesia.
No Cold War without the USSR. The rest of the 20th century is a calm and peaceful time for nations to cooperate.