From a lecture by Professor Bright Light of Royal Canterlot University:
"If one thinks about it, one can point out three events in history that effectively shaped the current world order into what it is now - the Reunification of the Griffonian Empire, the Great War, and the Black Crusade.
"The numerous events that resulted in the restoration of the Griffonian Empire under the rule of Emperor Grover VI once more led to a return of a large imperial power block in the continent of Griffonia that was rivalled only by the Riverlands. Meanwhile, the Great War was the bloody catalyst that helped Equestria fully become a modern superpower after inheriting the veteran military forces and reformed government institutions of Celestia's Solar Equestrian wartime regime as well as after rebuilding the nation's massive economy and industry which rode the waves of a post-war baby boom coupled with substantial immigration from other countries around the world.
"There was also the Harmonic Alliance which was intended to start healing the wounds between Equestria and the Changeling Lands after the Great War, replace the United Ponies Alliance as the world's premier alliance of harmonist nations, and set post-war Equestria and their allies up for much more involvement in the international stage. Now put a pin on that, actually. We'll touch on the Harmonic Alliance later.
"Anyway, in the aftermath of the chaos of the early 11th century, Equestria and the Griffonian Empire ended up possessing a potentially enormous amount of political and economic influence. All that was needed was something that would align those two worlds together.
"Enter the Black Crusade.
"After northern Griffonia (sans Vedina) fell to the Dread League, the situation looked bad for the Griffonian Empire and the River Federation as the undead hordes threatened to bring the war over to their homelands. Luckily, expeditionary forces from places like Equestria, Olenia-Chengelingia, the Crystal Empire, and New Mareland helped turn the tide. This was the first time anything big from Equus directly participated in continental Griffonian affairs, and soon, a friendship was blossoming particularly between Equestria and the Griffonian Empire.
"Make no mistake, however. The Griffonian Empire under Grover VI was already starting to lean heavily into harmonist ideas years before the Black Crusade. The Black Crusade was simply the final push needed to effectively bring the world of Equestria and the world of the Griffonian Empire into a sort of friendship, and this was made official when the Griffonian Empire and the River Federation joined the Harmonic Alliance with Wingbardy and Aquileia following soon after.
"And so one can probably see what happened next. Two of the most powerful nations in the world that just so happened to be ideologically aligned and a strong multicontinental alliance of like-minded countries with vast global influence led by those same two nations? It was a foregone conclusion, and notably, it was something that Princess Twilight Sparkle's post-war government was hoping for which is a topic we'll delve into at a later date.
"To end today's lecture, think of a car or a computer or some packaged food. There's a very good chance that whatever product you can think of, it was most likely made using resources extracted in Equestria or the Griffonian Empire and manufactured by an Equestrian or a Griffonian company. That fact holds true here in Equestria, and that fact holds true in the rest of the world as well.
"Now think of today's iconic shows and movies, popular cuisines, cutting-edge technology, influential laws, individual rights, numerous modern institutions... All of those most likely originated from Equestria or the Griffonian Empire.
"The point is that the events of the early 11th century paved the way for Equestrian and Griffonian political, economic, and cultural influence to spread all over and create the world we know today - an Equestrian-Griffonian world."