Baton Rouge is the capital city of the American state of Louisiana. Its the second largest Metropolitan city in the state, a growing technology centre in the US South, and ninth largest port in the USA.
This is the city's current flag:
It ranks 80th with a score of 3.95 for city flags by the North American Vexillological Association, so it is by no means the worst flag, but its by no means the best.
I redesigned the flag slightly:
I am not too sure on the shield. I generally don't like Union Jacks on shields but I think this one is probably unique.