forgiveness, fearing that they would share the same punishment as Bryennios and Basilakes; Nikephoros showed mercy and granted them amnesty, along with both gifts and titles. Nikephoros had originally considered Constantine Doukas as a candidate for his heir, as he had no children of his own, but he abandoned this after Constantine revolted against him. He then set his sights upon a distant relative, Synadenos Botaneiates, of whom almost nothing is known other than that he later married a niece of Alexios. Norman Duke Robert Guiscard of Apulia prepared to invade the Byzantine Empire in 1081 under the pretext of defending the succession of Constantine Doukas, who had been engaged to Robert's daughter Helena; at the same time, the Seljuks captured the town of Cyzicus. Alexios was entrusted with a substantial army to defeat the Norman threat but conspired with his relative John Doukas to instead take the throne for himself. Alexios raised a rebellion against Nikephoros and was able to quickly surround Constantinople and put it to siege due to the lack of a defensive army. Nikeophoros was unable to secure the support of either the Seljuk Turks or Nikephoros Melissenos, his traditional rivals, and thus was forced to prepare to abdicate. Nikephoros decided that his only choice was to abdicate in favor of Melissenos, who was nearby in Damalis in Anatolia, and sent messengers to him across the Bosphorus; however, these messengers were intercepted by George Palaiologos, a general of Alexios, who persuaded them to support Alexios. Alexios and his forces broke through the walls of Constantinople on 1 April 1081 and sacked the city; Patriarch Cosmas convinced Nikephoros to abdicate to Alexios rather than prolong the civil war. Nikephoros then fled to the Hagia Sophia and sought sanctuary inside of it. Michael, the logothete of Alexios, then escorted Nikephoros to the Monastery of Peribleptus, where he abdicated and became a monk. He died later that year. Daniel Maynard comments that both Anthony Kaldellis and João Vicente de Medeiros Publio Dias tend to characterize Nikephoros' reign as part of the Doukas dynasty, with Kaldellis stating that "Botaniates' reign was basically an extension of the Ducas dynasty", and de Medeiros Publio Dias stating that "His government is normally only seen as a prelude to the important, but at the same time controversial rule of Alexios I Komnenos". Reforms and domestic policy Nikephoros performed many acts to secure the support