Early modern urban parliaments suffered an increasing monopolization of political power that hampered urban development. To combat power monopolization, some Swiss city-states reformed their election systems by randomly selecting political representatives from a pre-elected pool of candidates. We implement a difference-in-differences design and find that lottery-based election systems improved the equality of distribution of political seats within parliaments. Lottery-based elections also had positive effects on trade tax revenues, trade volumes, and infrastructure expenditures. We explain this finding by showing that lottery-based election systems fostered the election of merchants to top political positions. *