In the mid-fifteenth century, Waikiki served as the center for Oahu's rulers.  During this time, the area's marshland was home to large fishponds and taro fields.  The rainfall that flowed down from the Ko'olau Mountain Range made agriculture possible, and the name Waikiki (spouting water) was bestowed upon the region.  You would have to fast forward all the way to 1927,... when the surrounding Ala Wai Canal was completed to drain the area, in order to understand how modern Waikiki came to be. Backtrack a bit to 1809 though, when King Kamehameha I first decided to move his court to central Honolulu to accommodate trading, and you'll see that Waikiki actually reverted to being a lesser-known suburb of Honolulu.