 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.Under the monarchy the economic imbalance between the Hutus and the Tutsis crystallized, and a complex political imbalance emerged as the Tutsis formed into a hierarchy dominated by a "Mwami" or 'king'.