The rising of 1180 and the Kamakura base
Yoritomo raised forces in Izu in 1180 and entered Kamakura later that year. The city already had connections with the Minamoto family; shrines and urban construction became part of its development as a political center. Rewards for service helped him bring warriors from different eastern localities into a common military following.
These warriors retained their own holdings, relatives and dependants. Participation in the coalition did not erase those relationships. Yoritomo's authority depended on recognizing established rights, rewarding service and allocating offices, creating increasingly organized ties between his leadership and local military families.
Land offices and the warrior network
After the defeat of the Taira in 1185, offices over confiscated Taira estates supplied opportunities for Yoritomo to appoint his followers as estate stewards. The destruction of the northern Fujiwara in 1189 extended his control in Mutsu and Dewa. Military success, recognition by the court and local appointments operated together.
A Kanagawa prefectural archival study explains that some warriors from Sagami acquired substantial offices elsewhere while retaining relatively small home holdings. Relatives or retainers could act as deputies. The resulting network connected distant lands with Kamakura and helped shape later movements and development of warrior families.
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The 1192 appointment and subsequent shifts in power
Yoritomo received the title of shogun in 1192. The appointment marked an important stage, but his base at Kamakura dated from 1180 and his authority had already expanded through war and appointments. The establishment of a headquarters, the extension of land offices and the later shogunal title describe different steps in the formation of warrior government.
After his death in 1199, the Hojo family of his wife, Masako, gained increasing influence. Competition involving the Hojo and leading military families changed the balance inside the continuing government. Yoritomo's personal career and the longer institutional history of Kamakura rule therefore follow related but distinct chronologies.