Firstly, it's important to say: what's Glamorgan? It's a historic, or traditional, county of Wales. It was formally abolished in 1974, but it resists as a "traditional county" i.e. as a place people still consider to have belonging. It's the flag of Glamorgan:
This flag is, actually, a kind of banner of arms (a rectangular version of the coat of arms) of Iestyn ap Gwrgant, the last Welsh ruler of Morgannwg (do you realize the name similarity?). It was an inspiration to many coats of arms of places in former Glamorgan. See examples:
Vale of Glamorgan
It even appears of the flag of the city of Cardiff, capital of Wales located on former Glamorgan:
This flag has everything to became the flag of the traditional county of Glamorgan: it's simple, distinctive, well-recognized and unifying (the examples I showed proved the last two). If you're interested on the campaign to a new Glamorgan flag (wherever you live), click here. If you want to find other county flag proposals, click here.
Comments are welcome!