Over the past fifteen years, collaboration between economic historians, archaeologists, and historians has produced a large body of quantitative evidence on wealth inequality in ancient and pre-industrial societies. This talk reviews what we have learned and where the frontier now lies. I first discuss measurement: how newly assembled global datasets of residential-unit and burial wealth, together with statistical methods that explicitly model bias and uncertainty, allow comparable Gini estimates across millennia and continents. I then turn to determinants, showing that farming technologies which raised the relative value of land and capital over labor — plough agriculture, terracing, irrigation — were associated with sharply higher and more durable inequality, and that early states supported and amplified this inequality despite limited state capacity. Finally, I present new evidence from the Roman Empire and outline how expanding data coverage and new evidence on markers of political interactions can open the black box of institutions in the long run.