DIARCHY

diarchy. [fr. Greek dy “two” + archein “rule”] A government jointly ruled by two people, such

as William and Mary of England. — Also termed duarchy; dyarchy.

“Dyarchy. A term applied by Mommsen to the Roman principate … a period in which he held

that sovereignty was shared between the princes and the senate. The term has also been given to a

system of government, promoted as a constitutional reform in India by Montagu and Chelmsford

and introduced by  the Government  of  India  Act, 1919. It  marked the introduction  of  democracy

into the executive of the British administration of India by dividing the provincial executives into

authoritarian  and  popularly  responsible  sections  composed  respectively  of  councillors  appointed

by the Crown and ministers appointed by the governor and responsible to the provincial legislative

councils  ….  The  system  ended  when  full  provincial  autonomy  was  granted  in  1935.”  David  M.[Blacks Law 8th]

Walker, The Oxford Companion to Law 386 (1980). [Blacks Law 8th]