The first centenary (1900-2000) of the establishment of agricultural cooperatives in the Greek countryside is an appropriate occasion for offering a critical retrospective of their operations during the 20th century. Initially, the causes of their delayed appearance and establishment in Greece are investigated. Subsequently, the large extension of agricultural credit, as well as the constantly increasing involvement of the government and banks in their internal affairs are described and analyzed. This analysis also focuses on the particular interwar conditions that favored the protectionism of the agricultural economy and the “State’s supervision” of cooperatives, an essential element of agrarian policy, even during the first post-war period. Finally, we examine developments relating to the cooperatives during the transition from dictatorship to democracy, namely, the subsequent legislative interference, doubtful investments, as well as the transformation of the organizations into an arena of self-interest for political parties and their leaders and into a means of implementing government social policy.