The Mauritanian Progressive Union headed by Moktar Ould Daddah won 33 of the 34 seats in the Territorial Assembly elections held in March 1957.[3] Moktar Ould Daddah was chosen as the Chairman Mauritian Advisory Council by France's fourth republic.[4] On 28 November 1958, a Constitutional amendment allowed the creation of a transitional Legislative Council, replacing the Territorial Assembly.