Justinian I
August 1 527 through November 14 527

Having most of the control during his uncle's reign, Justinian I started on one of the longest and greatest reign's within the history of the Byzantine Empire.  His expansions of the empire  were to reach the greatest of any emperor.  Unfortunately, this expansion came with a large cost of taxes and overextending the military.  In the east the Persians were regaining strength and Justinian I had to pay large tributes to maintain the peace.  His expansion did not just include the empire, but he also started one of the largest building campaigns in Constantinople with the church of St. Sophia being one of the greatest.