Idea for a short story
Seventeenth century Germany. A minor Duke, unable to afford an actual army, instead invests his money in a local artist. The artist also has some knowledge of alchemy and uses his skills to create a flag for the Duke so captivating that anyone who sees it is compelled to follow it. The Duke is able to use it to take command of enemy armies, soon building himself one of the largest forces, and largest domains, within the Empire. Unfortunately, with his new found power, he forgets all about the artist, who loses his living and is thrown out of the palace. The artist then starts touring the courts of rival nobles, making flags for everyone, and the Duke's new kingdom falls apart as quickly as it arose. Finally the artist makes a banner for himself, creating his own little state up in the mountains, where he can work undisturbed by politicking.