Simplify the following text for a Grade 10 native English-speaking person.
Original: Penang and Singapore were also considered to be administratively a part of the Presidency until they were incorporated into the Crown Colony of the Straits Settlements in 1867 .
Simplified: Penang and Singapore were also considered to be part of the Presidency until they became part of the Crown Colony of the Straits Settlements in 1867 .