Emblematic figures of the anti colonial fight, H Bourguiba and L.S.Senghor dominated, for a long time, by their powerful personalities the life of their people and left their print on the new States which they took over . It is the political paths of these two men which are studied in this work. However to apprehend them, it is advisable to place the two men in comparison with the context in which they appeared, who upheld them, who they represented, but also who they changed by their respective genius, and even those of whom they did not realise the evolution. l is also appropriate to show the dynamics of the two countries, the forces involved, the differences, for then placing the action of these two men in these contexts. The first part aims at taking stock of thirty years of Bourguiba regime. During the first ten years of its presidency, Bourguiba attempts to build a State of the "legal-rational" type conforming to Western modernity standards. But instigates at the same time a personal power which results in the setting aside, the lining up or the elimination of hostile forces to his hegemony. Fragile balance, whose precarity appears as his health declines. Twenty years of fight for his succession will follow then, on a foundation of acute economic crisis and serious social strain. November 7th, 1987, facing the drifting regime and the deliquescence of the State, his last Prime Minister decides to set Bourguiba aside for his incapacity to control the situation. The second part attempts to analyze the social, economic, political evolution of the Senegal State. It shows how after a phase of tightening up the regime, following the crisis of December 1962, Senghor is forced, under the pressure of serious events and the rise in social claims, to carry out a progressive liberalisation of the regime, making the Senegal reach political pluralism, from 1976 onwards. In 1980, 75 years old, he decides voluntarily to leave power, having taken long term care to prepare his succession.