This thesis examines urban political conflict in the late Middle Ages (c. 1370-1440) in Europe's most heavily urbanised regions, Italy and the Southern Low Countries. Conflicts have frequently been viewed in the context of an emerging state-controlled political order, and have been interpreted either as forms of disruptive disorder, or as affirmations of political processes shaped by states. This thesis suggests that urban conflict should be studied not in the context of a state-controlled political order, but within the political framework provided by the numerous semi-autonomous jurisdictional institutions inside and outside cities (such as guilds, parishes or contending outside powers). This pluralistic order of politics gave rise to a form of political order sui generis which expressed itself in two ways. According to a general logic of conflict (Part One), particular rationales for justifying conflict (Chapter One) and specific political practices ranging from concealed protest to urban warfare (Chapter Two) were embedded in this multi-faceted and shifting political framework. Action groups could be negotiated and renegotiated around the resources provided by the city's multiple legitimating institutions (Chapter Three). At the same time, such political institutions were configured differently in different cities, and this also generated a particular logic which lay at the basis of different systems of conflict (Part Two). Levels of conflict could, in fact, vary greatly between Bologna and Liege (Chapter Four), Florence and Tournai (Chapter Five), and Lille and Verona (Chapter Six), where, on the basis of different underlying political institutions, diverse practices of conflict and forms of association prevailed. The pluralistic order of politics itself was, therefore, a form of political organisation which crystallised around conflict. It gave rise to a logic which put conflict at the centre of the political order of late medieval cities.