The Arían Empire was the imperial phase of the Arian state, which lasted intermittently from circa November 2001 to August 2003. This was the time during which Aria was at the height of its power, influence, and size, defined by an autocratic domestic political system, an aggressive and interventionist foreign policy, a well-developed sense of national identity that manifested in numerous cultural undertakings, and paramount social influence within the wider Maryland civilization.
The beginning of the Arian Empire is variously dated to the admission of the Province of Renaldi in October 2001 (though documentation supporting this event is unclear), the signing of the Constitution of Rights on November 29, 2001, the admission of the Province of Nicholia in December 2001, or the admission of the Province of Atricia in January 2002. The Empire definitively ended on August 24, 2003, when stakeholders from across the country agreed to a series of reforms that resulted in the creation of the Arian Republic, a constitutional monarchy whose scale and power were much more modest than what was enjoyed during the imperial era.
For the great majority of its history the empire was ruled successively by two imperial houses, the House of Vontres and the House of Steele. The House of Tanver also briefly held the imperial throne. A fourth house, the House of Rendal, may have contributed Aria's only empress, but whether and under what circumstances this occurred is unclear. Between them, the three imperial houses of Aria offered four monarchs (Joseph, Powell, Pierce, and Andreas), with a fourth house and fifth monarch if the disputed empress Madeleine is included.
The Arian Empire marked the peak of both the Maryland civilization and Aria itself, and the imperial era is the period with which the Arian state is most closely associated.