The first three centuries of Zaydism in Yemen (around 900-1200) were characterized by a complex and heterogeneous political situation with several competing Zaydi sects and networks operating simultaneously. By looking closer at tax policies, this paper focuses on the relations between various political-religious Zaydi rulers (imams), their subjects, competing Zaydi sects, and other Islamic dynasties. Both legal and historiographic sources allow us to look at the tension between the ideal Islamic taxes such as the zakat and those taxes that were legitimized by “necessity” such as the ad hoc tax called maʿūna. Zakāt was mainly limited to ten per cent of the annual crop from rain fed lands, however, the maʿūna could be much higher. Especially by referring to the expenses of holy war against unjust enemy rulers, the Zaydi imams could justify increasing the taxes more than what the Islamic law would originally allow for. The Zaydi imams often faced internal opposition from other Ashrāf-clans or from scholarly Zaydi networks like the Muṭarrifiyya who made counter claims by employing competing theological doctrines. Due to the unstable political situation at this time, the borders between different Islamic sects were constantly shifting and local elites often had to quickly change their loyalty to Zaydi, Sunni and Isma’ili rulers. Local elites had a prominent role in enforcing the tax collection in their respective areas and they were often allowed to keep a significant part of the taxes for themselves. The interdependency between local tribal elites and charismatic Zaydi religious leaders is therefore important in understanding a region of Yemen where the ideology of tribal autonomy was strong. By looking at a limited field such as tax policies one can see a picture that transcends concepts like politics, law and religion, allowing us to better see the richness of the sources available to us and by combining history, Islamic studies and anthropology one can better understand the political and social processes of the time.