The history of cornbread is as old as corn itself! I know this sounds dreary, but it's true. In the USA, we've known about and eaten cornbread since arrival of the Europeans. The native Americans learned early to dry and grind corn into corn meal, the basic component of cornbread. When mixed with eggs and corn flour, the easiest and simplest of cornbreads can be made. Thin, dense, and flat, it was just the way to transport healthy food for long distances over periods of time without all the weight. Elsewhere in the world, you can almost always find some form of cornbread wherever corn is harvested for food.
Modern cornbread is made in much the same way it always has been, although there are as many ways to cook cornbread as there are variaties. The Mexican culture has brought quite the influence to cornbread in recent decades, as jalapeño cornbread and peppered cornbread are very popular here in Central Texas. Cornbread muffins and sweet cornbread are very popular in the Northeast, while we're unsure if people in the Northwest even eat cornbread. :)
Cornbread will be here for many years. It is very cheap and easy to make, can be prepared so that most anyone will enjoy eating it, and is very nutritious. Modern Americans associate it with several celebrations, including Thanksgiving and July 4th. I personally find it goes great with almost anything, but who am I to say what it is good with or not? It's just cornbread, EAT IT!