When the Emirate of Transjordan was established in March 1921, Shaykh Mithqal Pasha al-Fayiz was already on his way to attaining the top leadership position of the Bani Sakhr tribal confederacy. A few weeks later, he was recognized as their paramount shaykh, a position he kept until his death at the age of 90 in 1967. From the moment of his appointment, the elite status of Mithqal, and later that of his family and successors, was closely tied to the modern state; he was directly affected by the establishment of the Emirate of Transjordan. On the one hand, the gradual consolidation of state power inevitably came at the expense of his and the confederacy’s extensive autonomy. On the other, Mithqal took advantage of the new political structure to enhance his own political and economic position, and that of his family and tribes. By the late 1930s, Mithqal had emerged as the largest landowner and one of the richest and most influential men in the county. Mithqal’s connection to the Emirate entailed the need to modernize, as the new entity was a mandate state and was built in part on the model of the modern European state. This new political structure accelerated the pace of modernization, which had already been initiated by the Ottomans. This paper analyzes how Mithqal responded to these new developments, namely the process of state-formation over the 25 years of the mandate. It discusses the challenges Mithqal, as well as other shaykhs of his stature, had to deal with as part of the modernization process under British rule. As will be argued, Mithqal was amenable to adapt to the new modern conditions. More than any other shaykh in Transjordan, he was successful in finding new ways and resources to maintain his leadership and privileged position. Understanding Mithqal’s road to modernity entails the potential to further the understanding of the important, yet under-studied political and social functions of the tribal shaykhs in the Arab Middle East. A wide range of archival sources in Jordan, Israel and the UK, together with press reports and oral testimonies form the factual base of this study. The analysis draws on the ever-growing empirical and theoretical literature dealing with state-tribe relations and contributes to enriching our understanding of tribal societies in the Middle East in modern times.