My favorite coins of the late Roman period were issued to commemorate the moving of the capital to the new city of Constantinople. The story on these was told on the page that brought you here so we will skip to the examples:
Some mints, as here, used dative to dedicate the coin to the new city while others used the nominative. The Roma type was always nominative.
SMNA - - - - - - TR.P
Sacra Moneta Nicomedia (numeral A=1) - - - - - - Trier . Primus
Note that Western mints often used initials of ordinal numbers (P, S, T, Q) to designate workshops rather than the Greek numerals found in the East.