The Kamakura shogunate era is called by historians the Kamakura period and, although its end is clearly set (Siege of Kamakura (1333)), its beginning is not. Different historians put Kamakura's beginning at a different point in time within a range that goes from the establishment of Yoritomo's first military government in Kamakura (1180) to his elevation to the rank of in 1192. It used to be thought that during this period, effective power had moved completely from the Emperor in Kyoto to Yoritomo in Kamakura, but the progress of research has revealed this was not the case. Even after the consolidation of the shogunate's power in the east, the Emperor continued to rule the country, particularly its west. However, it's undeniable that Kamakura had a certain autonomy and that it had surpassed the technical capital of Japan politically, culturally and economically. The shogunate even reserved for itself an area in Kyoto called where lived its representatives, who were there to protect its interests.