Simplify the following text for a Grade 9 native English-speaking person.
Original: In 1955 , a year before western Nigeria became internally self-governing , Sir Ademola was appointed Chief Justice for Western Nigeria , thus becoming the first Nigerian head of the judiciary anywhere in Nigeria .
Simplified: Adetokunbo Adegboyega Ademola KBE was a Nigerian judge and former Chief Justice of Nigeria ( 1958-1972 ) . Before becoming the Chief Justice , he was Chief Justice of the Western Region of Nigeria .