Creole food evolved from a mixture of French, Spanish, African, and Caribbean cuisines. Cajun food comes from the land. Cajuns trapped or hunted for their meat and grew their vegetables and fruits. The Acadians brought their cooking techniques from France to Nova Scotia to Louisiana. They adapted what they knew to what they were given.
Cajun food is native to Louisiana because the ingredients are native to Louisiana.
There has always been much crossing over of the two cuisines. The Spanish dish paella, for example, may have evolved into a Creole dish called jambalaya, but the Cajuns ate it too, and changed the ingredients according to what vegetable was in season or what game was easy to catch. Bouillabaisse , brought here by the Creoles, developed into gumbo with the help of the Cajuns and some local ingredients. Many of the ingredients and seasonings are the same in Cajun and Creole cooking because of the natural availability and the melding of styles. Most Louisiana dishes are made with rice, a leading Louisiana crop.