Simplify the following text for a Grade 11 native English-speaking person.
Original: The Nagorno-Karabakh Republic Defense Army is the formal defense force of the unrecognized but de-facto independent Nagorno-Karabakh Republic ( NKR ) .
Simplified: The Nagorno-Karabakh ( NKR ) Defense Army was made on May 9 , 1992 as the formal defense force of the unrecognized Nagorno-Karabakh Republic , made up of Armenians .