regally
Concise Oxford English Dictionary © 2008 Oxford University Press:
regal/ˈriːɡl/
▶adjective of, resembling, or fit for a monarch, especially in being magnificent or dignified.
– derivatives
regally adverb.
regally adverb.
– origin ME: from OFr., or from L. regalis, from rex, reg- ‘king’.
'regally' also found in these Oxford entries:

