machiavelian

[From Machiavel (also called Machiavelli), an Italian writer, secretary and historiographer to the republic of Florence.]
Of or pertaining to Machiavelli, or to his supposed principles for conduct of government, as enunciated in his tract The Prince; politically cunning; characterized by duplicity, political expediency, unscrupulous cunning, or bad faith; crafty.
[1913 Webster +PJC]

Mach·i·a·vel·ian
Mach·i·a·vel·lian n.

One who adopts the principles of Machiavelli; a cunning and unprincipled politician.