Answer Wiki. Wikipedia has a fairly good summary - Modern art - defining it broadly as art from much of the second half of the 19th century through nearly 3/4 of the 20th. There's also a piece on Modernism in the arts from the mid-19th century through the present.
Another major difference that can be seen between Cajun and Creole is in their foods. The food of Creole is Afro-European with some French flair. On the other hand, Cajun foods have a French influence. One can also see that the two sects of people practise and love different music.
Cajuns mainly came from Acadia in nova Scotia and migrated down to the Lafayette/Acadiana region. The music is French based, and more folkish. the food is thought of as more spicy, but is really just seasoned heavily and is made of cheap ingredients. The Cajuns don't do the whole voodoo thing.