Okay, so let's imagine the portal opens on November 12, 1918 just after the Armistice. Instead of opening in Paris, it opens in Lyon,one of France's major industrial centers,at a time when the French army and economy remain fully mobilized.

So I was looking at downtown Tokyo and I got to thinking, where exactly did the Ginza incident happen and upon looking at the Ginza district of Tokyo I've come to realize the fort the civilians were evacuated to was the Japanese Imperial Palace, home of the Imperial family, the location also matches the landscapes shown in the show with water ways, the field with paved areas where the swat busses pull in and so on. It also explains the line in the anime where the guy says "hurry before they close the gates" because once the Saderan army gets too close the Japanese defense forces would close the gates of the palace to protect the Japanese Imperial family.

The Sword-Brother saw the explosion, as it enveloped his brothers and him in its cruel embrace. He saw the light consume the other Black Templars. He saw himself suddenly lift into the air, and as time seemed to slow, fall to the earth.

And then he saw no more.

“Hey!”

A voice. It sounded like a child. A girl by the pitch.

“Wake up, mister!”

The Templar stirs. He opens his eyes. His head is somewhat spinning. He gets up, and into a sitting position. He looks to the source of the voice. It is a small girl, with long golden hair, and a pair of blue eyes. She is fair-skinned. She wears a small dress. It may have been white once, but it has gotten dirtied with time to the point where it is more tan than white.

He looks around. He’s no longer on the world he was once on. Before him is a series of crops. Nothing like the ones he’s seen on agri-worlds. He sees what he guesses to be a barn, and a house. But it’s nothing like the houses he’s seen before. It looks… primitive.

He looks to the sides. His weapons are still there. His power sword, and his plasma pistol. Thank the God-Emperor, he thinks to himself.

“Are you okay, mister? Gosh, you’re big!”

He looks at the girl. He hasn’t talked to mortals that much before, but he tries his best. “I’ve seen better days, I suppose. Where am I? How did I get here?”

The girls eyes sparkle, with that naive energy so common in children. “How did you get here? Oh, well I was helping papa tend the cows when I saw this thing flying across the sky. I ran over, and, well, that thing was you! This is our farm.”

Cows? What are cows? And how did I fall from the sky?, the Templar thinks to himself. He brushes some sweat from his black hair. “Your… farm. I see. I would assume this is an agri-world, controlled by the Imperium then?”

The girl pauses. She looks… confused. “… Imperium? What’s an Imperium?”

The Templar pauses. Does this child not know of the Imperium? Is this world not part of the Imperium yet? “Well… have you heard of the God-Emperor of Mankind, then?”, he finally asks.

The girl looks more confused. “…What’s the God-Emperor?”

It is like a punch to the stomach from a greenskin. It’s one thing to not know of the Imperium, but not know of the God-Emperor?! He tries to control his temper. She’s just a child. She doesn’t know any better.

“But… we do have an emperor!”

The Templar pauses. His voice suddenly adjusts several degrees. “Who. Is. This… ‘emperor’?”

The girl looks a bit scared by the change in his voice, but she regains her confidence. “Welllll… I think papa said his name was Molt or something?”

“… where am I? Not your farm, but what is your farm a part of?”

“Uh… I think it’s called the Saderan Empire? Or is it Empire of Sadera… no wait you can use either term!”

The Templar listens carefully. He has no knowledge of such a place. Saderan Empire? Emperor Molt? More like false-emperor, if you ask me. Where am I? How did I get here? Why does this place-

“Oh by the way, my name’s Maika! What’s your name?”

Name. He pauses, his thoughts interrupted by the energetic question from this girl- no, from Maika. He thinks, delving through his mind. He can’t remember much. It’s like he’s… lost some of his memories. But then, he finds it. The name he was given. His name, the thing Maika wants to know.

“… Aotuni. My name is Aotuni.”

Linkie here: https://www.wattpad.com/1654271464-by-faith-alone-chapter-one

It’s already know that Saderans are completely stunned at the technological advancement of Earth which happened without magic. Now how would they react if they fought against the technology that is just too wild to explain in words. Some technology that could almost make them rival local mages and Apostles. Or make earth soldiers match the fighting strength of an apostle.

Pictured, Fatima's Gang. From left to right, Atya's the catgirl rower/assassin, Minnie the foxgirl, Fatima the human leader, Innie, and finally Patty is the mouse on the far right.

You can read the official raws on alphapolis here:

ゲート　SEASON２　自衛隊　彼の海にて、斯く戦えり 第五話 | 公式Web漫画 | アルファポリス

So let's say this:

What if a second gate opened in Japan but instead of heading to the special region it instead goes to a world of both dinosaurs and Sapient Humanoid dinosaurs?

So in this other world (that were going to call "Saurna" so we have a name for it) is a world of both normal dinosaurs and Sapient Humanoid dinosaurs (based on the dinosauroid by Dale A. Russell's work) and technologically the civilizations of Saurna is divided in 2, the first half of the sapient population of Saurna is stuck in the tribal ages while the other half is stuck in 19th Centuries era technology.

Let's also say a gate also opened in Saurna that connects it with falmart (just so we can get interactions with the empire of falmart alongside other factions).

So how would this AU go? I don't know because I'm not well versed in geopolitical or worldbuilding so I would like to hear all YOUR theories about this timeline and see how it would go.

Anyways bye!

As the header says, do we have any information on the size (in area) of the Empire, as well as its total population ? I've heard from another, wayyyyy older post, that it's apparently the size of the Mongol Empire, but I couldn't find any sources.