Gorilla Grodd predates Planet of the Apes by 4 years.
Grodd appeared in FLASH #106, Apr- May 1959 http://en.wikipedia.org/wiki/Gorilla_Grodd.
The French novel PLANET OF THE APES http://en.wikipedia.org/wiki/Planet_of_the_Apes_(novel) was published in 1963. Four years after the appearance of Gorilla Grodd.
Gorilla City, the place that most resembles the city in Planet of Apes movie, also appeared in FLASH #106.
Jack Kirby's KAMANDI was a nod to PLANET OF THE APES after DC Comics could not retain rights to the Book and Movie.
Ironically Kirby had already wrote a similar story to it in 1956 for Harvey Comics.
See this link for more info about KAMANDI and the Harvey story by Kirby: http://en.wikipedia.org/wiki/Kamandi.
So there PLANET OF APES. GORILLA GRODD is king of the talking Apes.
Go Forth and Do Well