Abstract: the article deals with the ideological and political factors and conditions that predetermined the inevitability of the sectional split of the American nation, and later the collapse of the American state after the efforts of politicians to reach another compromise agreement on slavery. The study of the ideological-political and party-political origin of the compromise suggests that the implementation of its provisions in any scenario led to a split of Americans because of their attitude to slavery and the collapse of the US Federal Union state. The sectarian contradictions of the South and North of the United States were so irreconcilable that all the efforts of their compromise resolution led to completely opposite results. Supporters of the Union’s preservation (unionists) completely diverged in their ideas about what it should be, putting the political initiative in the hands of extremist and sectionalist politicians. The definition of the 1850compromise as a turning point and the event of the prehistory of the civil war in the United States allows us to characterize with more thoroughness and depth the political events of the 50s of the XIX century in the study of the prerequisites and causes of the civil war of 1861-1865in the United States.
Keywords: sectionalism, secessionism, unionism, expansionism, problem of territorial spread of slavery, party-political struggle, doctrines of “southern rights”, “southern unity”, “sovereignty of settlers”, anti-slavery, pro-slave parliamentary coalitions, compromise solution of the issue on slavery