During the Second World War, during which time mainland France was occupied by Nazi Germany, Charles de Gaulle issued the Brazzaville Declaration, declaring that the French colonial empire would be replaced post-war with a less centralised French Union. The French Union, which lasted from 1946 to 1958, conferred a limited form of French citizenship on the inhabitants of the colonies, with some decentralisation of power and limited participation in political life for local advisory assemblies. It was during this period that the Nigerien Progressive Party ("Parti Progressiste Nigérien", or PPN, originally a branch of the African Democratic Rally, or "Rassemblement Démocratique Africain" – RDA) was formed under the leadership of former teacher Hamani Diori, as well as the left-wing Mouvement Socialiste Africain-Sawaba (MSA) led by Djibo Bakary. Following the Overseas Reform Act ("Loi Cadre") of 23 July 1956 and the establishment of the Fifth French Republic on 4 December 1958, Niger became an autonomous state within the French Community. On 18 December 1958, an autonomous Republic of Niger was officially created under the leadership of Hamani Diori. The MSA was banned in 1959 for its perceived excessive anti-French stance. On 11 July 1960, Niger decided to leave the French Community and acquired full independence on 3 August 1960; Diori thus became the first president of the country.