The Emperors and Celestia look at the mirror and go through it.
"Mein Kaiser, you're back after a few weeks! ...Is that a horse? With wings? And a horn? Lucky guess." Said the Chancellor.
"I am Princess Celestia, the newest member of the Central Powers. I have seen the future, if you do not win this war, all of your monarchies will be abolished, and Germany will elect a terrible person named Adolf Hitler into power, and he'll do many terrible things. Which is why Equestria, 10 million strong, shall help you." Celestia explained.
"10 MILLION MANPOWER?!" Exclaimed the Chancellor, "You're bluffing!"
"I'm a Princess, I don't lie. 10 million soldiers strong. Many fight for Equestria, fight for friendship and freedom. Friendship can't happen under these circumstances, if you lose, Earth will lose the little friendship is once had." The Emperors salute.
Equestrian soldiers march out of the portal, along with the Mane Six. Chanting the anthem of Equestria.
"General Shining Armor! Stand by my side!" Said Celestia. "Yes ma'am!" He replied.
"Allah's will...these Equestrians know loyalty!" Said Mehmed V
"Of course, there are 6 Elements of Harmony, loyalty is one of them, I happen to be it." Said Rainbow Dash.
The history of World War I resulted much better than in real life, much more was occupied, 2 more years of war, sadly, Franz Joseph still passed away, but the new Emperor, Charles I, rose up and assisted the Central Powers more. When 1917 hit, the Russian Revolution happened.
"What's going on in Russia?" Asked Twilight, Wilhelm chuckled, "About a century ago, a man named Karl Marx wrote a book called the Communist Manifesto, and some guy called Lenin took his word and is rebelling in Russia, this is great for the war efforts, even if Italy and the United States have since than joined, their resistance in futile! Thanks for your help, Equestrians!" Said Wilhelm II
"Huh, kinda like Starlight Glimmer." Said Twilight. Wilhelm received a telegraph from George V.
"Gonna surrender, cousin? Hah!" He reads it and asks for him to go to Buckingham Palace. "pfft, okay, carry me, Twilight." Wilhelm II rides Twilight to London, he goes into Buckingham Palace to see his devastated cousin.
"Nicky...he..." George wiped the tears from his eyes.
"What happened?" Asked Twilight.
"Our cousin...shot...his entire family...stabbed, even the children..." Said George V.
"Wait, what? I can never wish that upon somebody, especially my own kin, the Soviets...they're barbarians." Said Wilhelm.
"Oh no, that's horrible!" Said Twilight. Twilight thought to herself, and thought that peace was the option that suited the most. she trotted to Equestria. She goes into the palace. Luna and Celestia sat on their thrones.
"Celestia...we need a peace treaty between the two nations..." She explains everything to Celestia.
"Why...didn't I think of that before? I knew peace would be the right option, it's just...what you told me..." Said Celestia.
"I know." Said Twilight, "I reacted the same way." Twilight and Celestia got the leaders of the Entente and Central Powers together at a peace conference. Celestia proposed that they should be all allies, and that war and death aren't the answer. For what happened to Nicholas II was unforgivable by the standards of both sides. George V and Wilhelm II looked at eachother and hugged, than shook the hands of President Georges Clemenceau of France. Along with formally apologizing to King Albert for invading Belgium. The powers all came to an alliance.
"I propose something." Said Woodrow Wilson, president of the USA, "I think you might like it. I call it the League of Nations. Nations help eachother, co-exist with eachother. Solving conflicts peacefully, not through war."
"I like that idea, Mister President." Said Celestia
"Than it's settled, Equestria shall join the League of Nations! With your permission of course, Celestia." Said Twilight, Celestia agrees, and the Central and Entente powers are formally dissolved, forming the League of Nations. With that, most future conflicts never happened, no terrorism due to the existance of a Caliph, no Hitler because of Germany still being the German Empire, and peace because of The Ponies of Equestria having a presence on Earth. Life wasn't perfect, but as time went on, the worlds of Earth and Equus got more progressive, more forward thinking, Monarchies and Republics are balanced, and Communism isn't as big.
The ponies look at Berlin one more time before going back through the portal. Year 1939, in this world.
"Ein more thing, ponies...danke. For everything. I still mourn my cousin's death, but now...the world is at peace, danke for keeping everything at peace. By the way, that Adolf Hitler guy? He went on to become a painter, here's one of his portraits." He shows it to them.
"That's nice, be well, Wilhelm II." Said Celestia, she walks into the portal. Earth was shown the Magic of Friendship at one of it's darkest points in history. Now the world is at peace.