Simplify the following text for a Grade 9 native English-speaking person.
Original: East ( ern ) Francia ( Regnum Francorum orientalium ) , known variously as Francia Orientalis or the Kingdom of the East Franks , was the realm allotted to Louis the German by the 843 Treaty of Verdun .
Simplified: Eastern Francia ( Regnum Francorum orientalium ) was the land of Louis the German after the Treaty of Verdun of 843 .