Anyone poking around in early modern royal-documents from Spain, particularly from the sixteenth century, will come across “S.C.R.M.”
SCRM comes from SCCRM, a phrase that Charles V of Spain started using when he became the Holy Roman Emperor (Crowned by the Pope in 1530). SCCRM stands for “Sacra Cesárea Católica Real Majestade” (Holy, Imperial, Catholic, Royal Majesty). Under Phillip II SCRM begins to appear, which stands for “Sacra, Católica, Real Majestad” (Holy, Catholic, Royal Majesty).
Now, pick up your shovel, and continue digging in the archives.