Abstract This article analyses the structure and changes of large companies based on a new database of the 200 largest non-financial firms operating from 1913 to 1971 in Argentina. The main contribution of the research consists of the elaboration of the rankings of the 200 largest companies according to their paid-up capital between 1913 and 1971 and the construction of a database of large companies based on homogeneous sources and criteria. The study identifies the long-lasting presence of family-based diversified business groups and foreign multinationals from the first global period to the end of Import Substitution Industrialisation. It also shows that the presence of foreign companies among the 200 largest firms is higher than that identified in other countries. The study constitutes the first comprehensive research into big business in Argentina until the 1970s and a first attempt to identify the life cycles of the largest companies in Argentina.