Simplify the following text for a Grade 8 native English-speaking person.
Original: During the reign of Glele , his successor ( 1858-89 ) , the territory was ceded to France by a treaty signed on May 19 , 1868 .
Simplified: During the reign of Glele ( 1858-89 ) , who ruled after Ghezo , the area was given to France by a treaty signed on May 19 , 1868 .