Mount & Blade II: Bannerlord

To do this you need to find all banner pieces. You get the first piece by finishing the tutorial. Before you can get the other pieces, you have to complete the Neretzes folly quest. Once you have done that. You need to speak to Istiana and Arzagos. Say yes that you will help them. You should get the banner locations. The locations will be bandit hidouts, near the cites. Once you destroy the hideouts, you will get tge banners. Once have have them the achievement will pop.