The double headed eagle is an ancient symbol that has been associated with many empires including the Byzantine Empire as early as the 1400s, the Seljuk Turks, the Holy Roman Empire, the Russian Empire, and more recently, the Albanian Coat of Arms, adopted in 1992, or the Coat of Arms of Montenegro adopted in 2004.
The double-headed eagle was adopted by the Scottish Rite for use by the 33rd Degree Masons. In this image found in the Lakewood Cemetery at Minneapolis, Minnesota, the body of the double-headed eagle is copper with the crown and the radiating medallion above cast in brass. The eagle clutches a banner with the Latin phrase, “DEUE MEUMQUE JUS”, meaning, “God and my right”.
Gravely Speaking 
Interesting! Is this on a particular marker, or did you find it on many markers in this cemetery?
I only found a couple examples of this symbol in the Lakewood Cemetery but then, I did not have time to view every gravestone in what is a very large graveyard with tens of thousands of gravestones.
From Byzantium, the two-headed eagle spread to Russia after Ivan III’s marriage to Zoe Palaiologina (a niece of Constantine XI , the last emperor of Byzantine). Ivan felt that Russia was the true heir of the Byzantine empire and started adopting the double-headed eagle. It would later be incorporated as an important motif of the imperial families of Russia (the house of Romanov ), Austria-Hungary (the House of Habsburg ) and the royal family of Montenegro (the House of Petrovic ).
Fmaily of my grandmother was Tommasini, descendant from Imperial House Tomassini Leopardi of Costantinople. They have This Eagle in their coat of arms and the “motto” Spes mea in Deo (or Domino) est. (Giustinian-Eraclian dynasti)
double headed eagle in Albania has been used at least since 1400
“The Flag of Albania consists of a red field (background) with a black two-headed eagle in its center. The first sighting of Albania’s flag was on on November 28, 1443, when Skanderbeg (George Kastrioti), the national hero of Albania, raised his flag over the fortress of Krujë in defiance of the Turks who ruled the country”