I made a similar post several months ago. Feel free to read it here if you want context:
alternatehistory.com/forum/threads/worst-world-possible.543624/#post-24332023
WW1: Same as OTL
WW2: German victory by 1943, but it was very costly. Hitler survives an attempted assassination attempt by disenchanted officers, and he responds by outright purging the Wehrmacht. Himmler gains more favor from Hitler following the successful purge and for "solving" the Jewish question. A paranoid and mentally deteriorating Hitler eventually names Himmler as his new designated successor after finally being fed up with Goering.
Hitler dies in 1950, and Himmler's takeover of the Reich is swift and merciless. Goering and Bormann are terminated, along with Heydrich, who Himmler was beginning to grow distrustful of. Speer is named Deputy Fuhrer, and both Goebbels and Hess are sidelined, as the Party is powerless to stop the new Fuhrer. Any dissent soldiers from the former Wehrmacht are ruthlessly crushed, and the Waffen-SS becomes the Reich's new standing army.
WW3 (1950 - 1957): Fought between America and the communist regimes of Mao's China, a Beria-led Soviet Union, North Korea and North Vietnam. America unleashed its nuclear arsenal on the Asian continent, but it failed to deter the Communists. President MacArthur launches an amphibious invasion of China, but it results in catastrophic casualties for both sides. Millions of American soldiers die in the conflict and the Chinese were able to push them off the mainland by 1956, despite their death toll being even higher. The results in mass protests across the United States, and MacArthur's reputation was ruined.
Strom Thurmond beats Vice President Thomas Dewey in a landslide, after promising to put an end to the war despite his reluctance to do so. America withdrew from the Asian continent, including Japan, and watched as the communists reign supreme. Thurmond blamed the Northern elites and the Civil Rights movement for 'sabotaging' the war, so he has federal troops enforce segregation in the South in defiance of the Supreme Court. Civil Rights protests flare up in response and Thurmond orders federal troops to fire at the protesters, which results in the deaths of thousands of African Americans, including civil rights leaders and most notably Dr. King himself. This results in the 2nd American Civil War, but this time, it would lead to the permanent dissolution of the United States after many years of bloody warfare.
WW4 (1957 - 1960): During the Suez War, Himmler ordered for a nuclear bomb to dropped on London amid a massive air raid. This led to the deaths of the British Parliament and the Royal Family. A demoralized Britain surrenders to the Germans shortly afterwards, which enabled the Waffen-SS to march into Israel alongside the Egyptians, Syrians and Jordanians. Palestine is established while both concentration camps and death camps are prepared, in the surrounding desert regions, for the captured Jewish populace.
A jubilant Himmler, after seeing the collapse of America, decides to launch their "final" war against the Soviets. China joins in on the side of their Russian allies and Mao throws millions of his men on the frontlines to fight against the Germans. Tens of millions of Chinese soldiers die to lack of winter coats and being subjected to the full onslaught of Germany's nuclear arsenal. Despite that, Mao continued to send soldiers as the Germans began to run out of manpower and equipment. Himmler, along with Speer, gets overthrown and executed by his second-in-command Kaltenbrunner, who conspired with Goebbels against the spectacled madman. Goebbels becomes the new Fuhrer and reluctantly signs a white peace with the communist nations, but then preceded to enact his own revolution in the war-torn Reich.
WW5 (1965 - 1970): After the conclusion of the last war, Mao concluded that China was entitled to rule over all of Siberia after they did most of the fighting against the Germans. The Chinese successfully conquer all of Siberia by 1963 and then turn their attention on the tumultuous German Reich. In 1965, they launch a surprise invasion of the heavily-underpopulated territory of the Reich's eastern puppet states. Goebbels declares total war against the "Asiatic Horde" and assembles a Axis coalition against the Chinese and their communist allies. Despite the sorry state of the Reich, they put a decent defense of their territory because of fear among the Axis populace of a Chinese takeover, and because the Chinese hemorrhaged so many soldiers during the last few decades (but their massive and unchecked birth rate meant that Mao still had millions of meat-shields at his disposal).
By 1970, after an even more bloody war than the previous one, the Chinese fully conquer the former Soviet Union and "liberate" many of the Slavic civilians that were forced into slavery. Even in the face of a Chinese invasion of Germany itself and widespread panic in the streets of the Reich, Goebbels refused to surrender. So Kaltenbrunner had Goebbels arrested and executed for his delusional stance. Kaltenbrunner then proclaimed himself as the new Fuhrer and managed to negotiate a peace with Mao. In exchange of recognition of Chinese annexation of Germany's former Eastern slave states, Germany and the remaining Axis nations would be spared. The Chinese accepted this, because they knew that they were no position to conquer and occupy a hostile population of fanatic Germans yet.
WW6 (1981 - 1991): It had taken several years for Germany to stabilize into a respectable war footing. But an elderly Kaltenbrunner knew that the longer he waited, the stronger China would become. He, and the remainder of the old party and SS leadership, decide to invade the communists one last time, on the 40th anniversary of the Operation Barbarossa. Mao was long dead by now, and Deng Xiaoping was in charge of the People's Empire of China. China's demographics were still recovering from the previous world wars, but millions had already begun to rapidly colonize Siberia and now were settling into the rest of what used to be Russia. Because of the unprecedented land grabs unseen since the Mongols, the Chinese have no incentive to enforce any limitation of children being born, at least not yet.
The Germans launched a coordinated attack, along with the other Axis nations, with millions of troops pouring into the new Chinese land. The Germans had better equipment and were craving for revenge as they had everything to lose. The Axis initially took back a huge portion of their former eastern conquests, but the Chinese gradually countered this with more manpower. And this time, the Chinese were far more prepared for winter warfare. The war reached a bloody standstill for several years until the German economy began to collapse from the pressure. The German populace was fed up with SS rule, and so rebelled on mass. Kaltenbrunner ordered for his soldiers to open fire, but instead they joined the protesters. A coalition of moderate Nazi officials assassinate Kaltenbrunner in 1987, and promise the German populace major reforms after the war's conclusion, with the elderly and schizophrenic Rudolf Hess becoming the new Fuhrer as a unifying figurehead.
The Germans attempt to sue for peace, but the Chinese have none of it. They are now intent on destroying Nazism and reducing the European continent into several socialist tributary states. The Germans would hold on for 4 more years until the Chinese finally invaded the country itself. The German government, followed by the rest of the Axis nations, would surrender to the Chinese and concede to their demands in exchange for greater autonomy, which was ultimately accepted. And at long last, the final World War would conclude in 1991 and the Chinese would emerge as the world's sole superpower. America would still be divided and Britain would be too powerless to pose a serious threat to China. Now, China's control over Eurasia would not be absolute, as India would emerge as a formidable rival to Chinese hegemony. But that's about it.
And that's how there could've been a grand total of 6 World Wars and subsequently be the Worst World to live in.
