Lyric discussion by cyberpunksurvivor 

My theory is it's inspired directly from the thirty-year conflict in the mid 15th century for the throne of England: the War of Roses.

The "crimson tide" would be the blood spilled in the conflict or the blood in the seas. "The promise of a clean regime" would literally mean the hopes of a king to restore order. "The colors of the crown" would mean the two main factions of the war: the white rose House of York and the red rose House of Lancaster. Mary could be the Queen of Scotland Mary of Gueldres who was an ally of Lancaster. The song title and main line "Monarchy of Roses" would therefore be a direct reference to the above-mentioned houses and the roses they represented. The "Holy tears of Ireland" could be a reference to Richard of York's post as its Lieutenant and how the war spilled over into the nation. The "cross of the former queen" could refer to the previous queen or her symbol the fleur de lis.

I first took it for a straight-up reference to Catholicism, but the "Monarchy" stood out like a sore thumb.

@cyberpunksurvivor Lol that is what i thought, yay, now i can send to my british friend who loves rhcp!

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