Much of the so-called Age of Santa Anna in the history of independent Mexico remains a mystery and no decade is less well understood than the years from 1835 to 1846. In 1834, the ruling elite of middle class hombres de bien concluded that a highly centralised republican government was the only solution to the turmoil and factionalism that had characterised the new nation since its emancipation from Spain in 1821. The central republic was thus set up in 1835, but once again civil strife, economic stagnation, and military coups prevailed until 1846, when a disastrous war with the United States began in which Mexico was to lose half of its national territory. This study explains the course of events and analyses why centralism failed, the issues and personalities involved, and the underlying pressures of economic and social change.