As you build settlements and expand your influence in the wasteland, it seems to me that the Commonwealth is on its way to become a post-war nation, much like the NCR out west, and thus, they'll need a national flag. I imagine the Minutemen will become the de facto army of the Commonwealth, and their emblem will be that of the army, but perhaps elements of it could be present in the civil flag. I recommend checking out Okiir's work on deviantart to get a feel for what I mean. http://okiir.deviantart.com/art/FALLOUT-Flags-Seals-and-Emblems-of-the-UTC-650103870 Many of the local flags in the Massachusetts and New England area are heraldic in 18th century style, often blue with a motif in the center, see states flags of for example Maine, Vermont and New Hampshire to see what I mean. If you're building castles in the Commonwealth, maybe you'd like to see flags in a heraldic style depicting wasteland creatures like radstags, yao-guai and deathclaws. So anyway, post your best suggestions for flags of the United Commonwealth and post-nuclear heraldry! I'm working on some stuff right now, but it's all still very much in the conceptual phase, so I'd love to hear some of your ideas.