Article dans une revue: This paper suggests a new explanation for changes in economic and population growth with a long run perspective, emphasizing the role of land in the development process. Starting from a pre-industrialization state called the "Malthusian regime", land and labor are the main production factors. The size of population is limited by the quantity of land available for households and by incomes. Technical progress driven by a "Boserupian effect" may push the economy towards a take-off regime. In this regime, capital accumulation begins and a "learning-by-doing" effect in production takes over from the "Boserupian effect". If this effect is strong enough, the economy can reach an "ultimate growth regime". In the different phases, land plays a crucial role.