The flag of Marmarica
There isn't much to say about the flag of Marmarica. It's brown is the color of Marmarica, and the blue could refer to the sea, specifically, the Mare Internum, because Marmarica borders the Mare Internum. The circles look like waves, which could also refer to the sea. While the flag of the Union of Cleoptais has many circles, or suns, thingies representing a new dawn, et cetera, and has a unique flag because of that, Marmarica also does have nine circles, more than the Union of Cleoptais. Somehow, the Union of Cleoptais are unique for their flag, and Marmarica isn't. It's logical though, seeing as Marmarica only is a province of the Kingdom of Bruis, and who ever studies flags of provinces (that was a rhetoric question).
The flag of Marmarica under the Kingdom of Bruis
As most of the time happens, the Kingdom of Bruis simply added a border around the flag in their color, brownish red.