This project aims to describe and analyse the main patterns and drivers of regional economic inequality in Europe and the Americas in the long run. In this regard, we hypothesize that the current economic landscape has been the result of a long and complex process, which has been strongly influenced by geography, institutions and policies. This process, in turn, has shaped the extent and evolution of regional income inequality in Europe and the Americas. Despite all the socioeconomic changes occurred since the mid-1800s, reversals of fortunes and/or economic growth miracles are hardly observed. It appears that spatial inequalities in Europe and the Americas present few discontinuities, that is to say, are rather persistent over time. However, the Regional Economic History of European and American countries differ widely. In fact, this diversity provides a set of case studies to examine what are the proximate causes of spatial inequality at different levels, e.g. regional productive specialisation, public policies, geography, etc. A deep-rooted economic analysis of regional inequality will thus allow for a better understanding of the past, which might be useful for academics, practitioners (i.e. policy-makers), and the general public. With this in mind, the lessons from the past could be of much help and interest for current debates on regional inequalities, territorial cohesion, and public policies. However, and despite the enormous changes occurred from 1850 to the present, more continuities than ruptures may be observed in the economic landscape. In this sense, we argue that deep forces, particularly institutions and geography, have had a permanent influence in the spatial distribution of regional incomes.