Mark Koyama and Jared Rubin's 'How the World Became Rich' surveys the major explanations for why sustained economic growth emerged when and where it did, providing an accessible introduction to one of the most important questions in social science. The authors, both economic historians, examine theories that emphasize geography, institutions, culture, demography, colonialism, and state capacity, assessing the evidence for each without privileging any single explanation. They show how different factors may have been decisive in different times and places, and how various causes interact in ways that simple monocausal theories miss. The book covers debates about why growth began in Northwestern Europe rather than China, why some former colonies prospered while others stagnated, and why the Industrial Revolution happened in Britain. Koyama and Rubin write clearly for general readers while engaging seriously with scholarly literature, making complex economic arguments accessible without oversimplifying. They are honest about what remains uncertain and contested, presenting economic history as an ongoing inquiry rather than settled science. Readers seeking to understand why some societies are wealthy and others poor will find a comprehensive and balanced guide to the leading explanations.