Wilfried Silbergeld

"Wilfried Silbergeld had been ruling Gerasecia since then after he left Equestria for a mission to colonize a part of the Pony World. His younger sister named Silvia was badly killed by those five girls who made this murder a mystery. I don't know why we're seeing a murder like this. Now this is getting a hundred times worse than the Jack the Ripper murders..."

--Su Ji-Hoon, The Rise of Gerasercia's Anschluss

Wilfried Silbergeld is the German emperor of the Federal Republic of Gerasecia that he is the adult Earth pony who lived in locations of Equestria formerly and Gerasecia later with his younger sister,

As a German Earth pony, he led his own ponies to made their own economy and their own socials, which them will founded their own army and later made the born of the Federal Republic of Gerasecia, which located in the Pony World and an part of Inkwell Isle Four like other countries in the Pony World

And later, he have his wife who was the empress of Gerasecia and have federal army with his civilized ponies that he will become a German emperor for leading Gerasecia and the civilized ponies. When he have his own wife, they and Silvia Silbergeld will take care of 7 their childrens (including sons and daughters)

Until the USRAC War, his sister Silvia Silbergeld has been killed and made all of his 7 childrens have been kidnapped by a Belkan Grey Men pony member disguised as Princess Celestia and the Global Liberation Union members disguised as Ruby Ramirez,Gabby,Dorothy Ann Rourke and Fiona Frizzle that it will made him doubting someone killed his sister and kidnapped his childrens,so that he found  a cursed note which has been left by a Belkan Grey Men pony member that framed Princess Celestia like a note which framed Mr. Krabs 

However, it will caused the rise of Gerasecia's Anschluss and later joined the New Central Powers for his revenge,find all of his children and capture Princess Celestia,which starting declare war on Equestria due to have fully-armed and anti-magic resistance to attack on Canterlot in during USRAC War.

When Princess Celestria has been captured, he don't need to annex Equestria for interrogation and doubt about her killed his sister and kidnapped his childrens. Therefore, Princess Luna or the Mane Six (or the Equestria Girls) with the Grand Alliance find out about the death of Wilfried's sister but later found all of his childrens (who escaped from Belkan Grey Men base after Belkan Grey Men members kidnapped them)  in a adandoned house of the Sire's Hollow,which realize about the behind of his sister's death and kidnapping all of his childrens.

After The Journey Home song being spread, he realize the behind of his sister's death and kidnapping all of his childrens that he can apologize and release Princess Celestria and all of Equestria after he,Gerasecia and his royal family reunioned all of his childrens,which start fighting at Belkan Grey Men for revenge.