Bratwurst is German. Pure and simple. It comes from a country that takes sausage so seriously, they have laws about it. Polish sausage, or kielbasa, is from Poland. It’s basically the national food, and they don’t mess around.
One is a proud Bavarian. The other is a hearty Slav. They’re like cousins who yell at each other at family reunions. But they’re both delicious.