We present a model of vine-growing specialization in the municipalities of the province of Barcelona in the mid-19th century that explains how a comparative advantage arose through a process deemed to be one of the starting points for Catalan industrialization. The results confirm the roles played by the ‘Boserupian’ population-push on land-use intensification and the ‘Smithian’ market-pull in a growing demand from the Atlantic economy. They also stress the conditioning function of agro-ecological endowments and socio-institutional settings related to income inequality. Vineyard planting gave rise to less unequal rural communities until 1820, but inequality grew again afterwards.