The biography of the ‘Alid rebel Yahya b. ‘Abd Allah b. Hasan b. Hasan b. Abi ?alib (d. 187/803) raises a number of important theological problems for Zaydi scholars. Yahya first appears as an ardent supporter of the failed rebellion of al-?ahib Fakhkh Husayn b. ‘Ali in 169/786. His enthusiasm is contrasted with M?sa al-Ka?im’s (d. 184/800) (the 7th Twelver Shi‘i Imam) refusal to support the revolt and establishes his rightful claim to the Imamate from the perspective of later Zaydis. This claim is furthered by Yahya’s actions after the collapse of the rebellion as he first sends his brother Idris (d. 175/791) to organize an uprising in North Africa and then leads his own revolt in Daylam around 176/791-2. It is at this point that Yahya becomes more problematic for Zaydi scholars. The complications arise with his decision to sign an agreement of safe-conduct (aman) with the ‘Abbasid caliph al-Rashid (r. 170-03/786-809). According to most reports, Yahya remained free under the agreement for the eleven years and received a large caliphal stipend. This development forced Zaydi scholars to account for an Imam who (apparently) renounced armed rebellion and came to terms with a tyrant in direct opposition to the Zaydi doctrine of the Imamate. This paper explores how Zaydi scholars (operating at a time of Hadawi dominance in Yemen) remembered and/or justified Yahya’s Imamate. The analysis specifically focuses on four Zaydi scholars: Ahmad b. Sahl al-Razi (d. late 3rd/9th century), al-Isbahani (d. 356/967), al-Natiq Yahya b. al-Husayn (d. 424/1033) and ‘Ali b. Bilal (fl. 5th/11th century).