"Information is victory," - Romanos V's famous maxim.
Romanos V, as an Emperor, proved a turning point in Roman fortunes that had been in decline since the death of Manuel I Komnenos in 1180. His rise to power was unexpected, as he and his brother John had only been minor Pronoia holders in Anatolia prior to the disasters wrought by Alexios III Angelos which forced the failed Emperor to empower several Pronoia holders in order to try and stem the tide.
Romanos would, as many had before him, take his newly given power and turn on his overlord--although his efforts to play both fronts and divide his army between himself and his brother in order to ensure that the Anatolian front was not lost almost, in turn, lost him his bid for the Purple. Romanos was lucky in that the man he faced was a craven coward who would fail to destroy him outside Constantinople before trying to flee; only getting himself killed.
His personable nature and inherent verbal skill would allow him to make several allies, notably the Patriarch George II and his successor Michael I--as well as giving him a wide pool of skilled personnel to draw from for the benefit of the Empire such as the skilled Shipmaster Bardas Isandos and several 'star-generals' such as John Klephos and David Komnenos.
Throughout his reign however Romanos proved to be more than a usurper; reforming the bureaucracy, laws and military--as well as proving defining in the defense against, and later victory over, the 2nd Bulgarian Empire led by Kaloyan. In his reign he specifically reformed the coinage, destroyed the powerbase of the nobility (although this would later come back to bite him during the Latin Siege of Constantinople), reformed several laws and practices--and through the semi-joint leadership with his brother John, would reform the army into one capable of defeating both the Bulgarians and Turks in battle. This was all compounded with Romanos' unique skill with the 'carrot and stick' policy that few Emperors in the Empire could master, such as Basil II, which allowed him to cow the Bulgarians, and the Latin Crusaders who had attacked Constantinople.
His main failure however was, through his reforms, treading the same path as previous Emperors; thus repeating some of the same mistakes--notably the reformed army, while loyal at first, began to fracture in loyalties the further it got away from the Capital, which would result in a minor rebellion that claimed the life of his brother--as well as his failure to identity with the previous works of the Empire and firmly resettle the last retaken lands in Anatolia with loyal subjects, which in turn caused a major rebellion.
His greatest victory was his patronage of construction and repair projects, as well as the general improvement of the Imperial Economy (also unshackling it from the Italian Merchant Republics through his victory in the Latin Siege of Constantinople); only added to by his diplomatic efforts that had seen Bulgaria and Armenian Cilicia become important 'partners' in the Empire's sphere--while also building the first bridges between East and West in centuries with his noted friendship, and later father-in-law status over, the Holy Roman Emperor Frederick II. His efforts to refurbish Constantinople when possible would leave a firm bedrock for future rulers to rely on.
He would bequeath a strong, if tenuous, Empire to an adult male heir who was competent of mind and body at the time of his death; creating the long term stability the Empire needed.
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Statistics by the end of his Reign;
Population; 9,200,000~
Size of the Mobile Army; 40,000~
Direct Manpower Pool; 100,000~
Navy Size; Roughly 100 ships strong, 1/4 of which are purpose-built warships, the rest either refitted merchant vessels or troop ships.
Treasury Status; Semi-Full
Debasement Status; Near-nil
Status of the 'Three Organs'; Cooled, and cooperative