Sayyids might have wished to rule Yemen singlehandedly, but they had to deal with the much more numerous tribal populations of the region. These tribes traced their ancestry back to pre-Islamic times and saw themselves as heirs of an ancient social and political system. Without the support of the tribes, the Zaydi imamate was not viable.

The Imams employed tribesmen as soldiers. The tribes also provided scholars and judges who formed the backbone of the Zaydi imamate’s administration. Scholarship was an important activity for sayyids as well, and the Zaydi Imams were expected to be accomplished scholars.

Thus, scholarship, as much as affairs of the state, formed a close link between the imam and the tribes.

While the history of the Zaydi imamate is in many ways limited to Yemen, the Zaydis' scholarly links extend beyond it. One important episode in the history of Zaydism in Yemen was the transfer of knowledge from Iran in the eleventh century. The oldest Zaydi/Yemeni manuscript in the Leiden University Library collection is, in fact, a work from outside of Yemen. This speaks to the long history of connections between Yemen and the broader Muslim world.