istorical IR scholarship increasingly treats the second half of the nineteenth century as a time of transformation. Growing “interaction capacity” spurred new patterns of international organization and international law amidst inter-imperial cooperation and competition. Though it has received little attention in Historical IR, Mexico was at the centre of these occurrences – not only as a victim of imperial aggression but an active proponent of alternative visions of liberal and republican international order. From 1859 to 1867, the country saw a major debt crisis and a related intervention.

The Trump presidency generated concern about democratic backsliding and renewed interest in measuring the national democratic performance of the United States. However, the U.S. has a decentralized form of federalism that administers democratic institutions at the state level. Using 51 indicators of democratic performance from 2000 to 2018, we develop a measure of subnational democratic performance, the State Democracy Index.