Mehmed's imperial plans went further and aimed at conquering Rome itself, thus reuniting the Empire in a way it hadn't been for nearly eight centuries. His Italian campaign started in 1480 with the invasion of Otranto, but was cut short by Mehmed's sudden death on . None of his successors renewed that endeavor. Instead, they repeatedly (albeit never successfully) attempted to conquer the capital of the rival contenders to the Imperial Roman title, with a first siege of Vienna in 1529 and a second one in 1683.