The Italian Social Republic (Repubblica Sociale Italiana, RSI) was a puppet state established in northern Italy during World War II. It was formed in September 1943 after the fall of the Fascist regime led by Benito Mussolini, who was rescued by German forces. The RSI existed until April 1945 and was heavily influenced by Nazi Germany, which provided military and economic support. The government of the RSI was characterized by its authoritarian rule and continued the Fascist policies of the previous regime. It faced resistance from various partisan groups and was marked by internal conflicts and a lack of popular support. The republic ultimately collapsed as Allied forces advanced, leading to the end of Fascist rule in Italy.