Simplify the following text for a Grade 9 native English-speaking person.
Original: After the breakup of Yugoslavia in 1991 , the name of Macedonia became the object of a dispute between Greece and the newly independent Republic of Macedonia . In the south , the Republic of Macedonia borders the region of Greek Macedonia , which administratively is split into three peripheries ( one of them comprising both Western Thrace and a part of Greek Macedonia ) .
Simplified: Greece and the Republic of Macedonia are arguing over the name Macedonia .