Colonial militias shaped the republican armed forces, so the first section analyzes the Iberian origins of militias and during the conquest, their reform in the eighteenth century and during independence. Focusing on the development of notions of citizenship during the Age of Revolution and exploring the importance of the fueros and uniforms as incentives for participation. Colonial authorities grew wary on American subjects participating to wear fancy clothes and having their own corporate court. I also study how colonial administrations dealth with militias and the impact of militarization during Tupac Amaru’s rebellion and the first military campaigns after Napoleon’s invasion of the Iberian Peninsula. In a second section, I study the British, North American and French armed forces to compare them with the ones of the Spanish. I do this firstly because these armed forces were the most formidable at the time and there were important similarities and differences between them. And secondly, because it was precisely in these places where the ancient ideas of soldiers as citizens and citizens as soldiers was revived during the revolutionary era.