Partido Socialista Brasileiro (1945-1965): elementos de formação institucional

This article will address the creation of the Brazilian Socialist Party, from the elements of institutional formation to its electoral performance since 1945. A historical-comparative analysis will be proposed between the establishment of the PSB and the major parties of the 1946 Republic — PSD, UDN and PTB. The objective will be to establish possible causes of the unique organizational development experienced by the PSB, through the observation of embryonic organizational traits and the organization-environment interaction in the first years of its existence, as well as electoral data from the period. The results show the causal sufficiency of the state origin for the consolidation of the reference parties, absent in the case of the PSB.