The PC Group were originally the remnants of the decimated mercenary brigade Kogusar's Black Legion, they went by that name until about 6th level (though they were led by PC Fighter Sir Henry Lankaster)
After about 6th level, they had made a good name for themselves in the employ of the completely incompetent Lordling Prince Aston Clarkly, and as his stock rose at court (largely due to their successes), so did theirs. Around this point they were known simply as The Black Legion, having dropped most references to their long dead, and unloved captain. They purchased "court uniforms" for themselves. Very military in bearing, but not armor (more like a gestapo uniform minus the hat and trenchcoat if truth be told).
When Sir Henry, in recognition of The Black Legion's victory over The Grey Hags of Moleryn, was named Baron of the Western Reaches by Prince Aston's father, Duke Harmon Clarkly, His Grace found it beyond tolerance that one of his lynchpin Liegemen should be surrounded by a "Gaggle of Coin Soliders", and granted the rest of the group Peerages (raising them all to Knighthood) and insisting that they form a knightly order.
Thus they are currently known as The Loyal Order of the Black Legionairres.
They have added ermine and and cloth-of-gold capes to their uniforms, as well as remaning their tower theri' Chapter House".