蔡和森在法国期间酝酿和发起了中国旅欧青年组织,回国后受党中央指示,参与社会主义青年团第一次全国代表大会的筹备工作,起草青年团纲领等文件,为青年团大会召开做出了重要贡献。蔡和森当选为团中央执行委员,担任团中央宣传部主任,在团刊《先驱》上宣传党的政策,同时指导建立和整顿各地青年团组织,为青年团的发展也做出了重要贡献。 During his stay in France, Cai Hesen brewed and launched the China Travel Europe Youth Organization. Upon returning to China, he was instructed by the Party Central Committee to take part in preparations for the first National Congress of the Socialist Youth League and drafted a document for the Youth League. The document was prepared for the Youth League meeting The important contribution. Cai Hesen was elected Executive Chairman of the CYL Central Committee, Director of the Central Propaganda Department of the CYL Central Committee, promoted the party’s policies on the “pioneers” of the CYL group, and at the same time, guided the establishment and rectification of CYL organizations throughout the region and made important contributions to the development of CYL.