Roman Army Heraldic Symbols

[Nathan Ross]

The facing horses are exclusively British or so it seems, but facing dolphins, cats, dragons even are even more found in late Roman military buckles.

You're quite right - they are belt buckles, not brooches. And I read them as seahorses, but they could be dolphins or sea serpents:





The ones showing actual horses seem to be usually facing outwards:



As for cats... Cats?? :-)