Jambalaya originated near New Orleans. In Louisiana's history, there was a time, it was controlled by the Spanish. During that time, the French tried to make Spanish Paella but couldn't find saffron. Instead, they used tomatoes, creating what is now known as Creole jambalaya. It's usually red in color. It gets the color from tomatoes. As this dish made its way out of the city, tomatoes were less accissible, leading to the creation of Cajun jambalaya.
I've been to that area and had some jambalaya before. It's spicy though. The jambalaya rice and spices come in a box too. You can find that in some grocery stores.
