Simplify the following text for a Grade 15 native English-speaking person.
Original: Those members of the Order that did not fight managed a large economic infrastructure throughout Christendom , innovating financial techniques that were an early form of banking , and building many fortifications throughout the Mediterranean and the Holy Land .
Simplified: Non-combatant members of the Order managed a large economic infrastructure throughout Christendom , innovating financial techniques that were an early form of banking , and building many fortifications across Europe and the Holy Land .