In the 19th century, the state became far more centralized, and the history far more precise. Expansion continued, reaching the shores of Lake Kivu. This expansion was less about military conquest and more about a migrating population spreading Rwandan agricultural techniques, social organization, and the extension of the political control of a "Mwami". Once this was established camps of warriors were established along the vulnerable borders to prevent incursions. Only against other well developed states such as Gisaka, Bugesera, and Burundi was expansion carried out primarily by force of arms.