diarchy

The diarchy, however, as might have been expected, was found not to work very successfully in practice.

Diarchy, dī′ar-ki, n. a form of government in which two persons are jointly vested with supreme power—less correctly Dī′narchy.

This diarchy was to hold for both the central and provincial governments.

So ran the mind of him whom the mocking Gog and Magog of the deserts diarchy had put on a false trail to desolation.