By the early 1900s Sidiyya Baba was already a strong ally and confidante of the colonial administration.  He was ready to intervene on matters outside of his jurisdiction and to assist the French in difficult situations. The most striking example is the one that began this essay, and concerns Amadu Bamba after his first exile. Bamba had returned to Senegal and his Baol homeland in 1902, thanks to the intervention of Baba, Deputy François Carpot, and other influential people. But his presence proved disruptive to several chiefs who were seeking to consolidate their authority under the colonial system. Their complaints affected French thinking. Martial Merlin, Secretary General of the Government General, organized the arrest and second exile of Bamba, this time to Trarza and the orbit of the Sidiyya.  Baba's son-in-law, Shaikhuna, was present at the arrest and facilitated the transfer in May, 1903.

The period of Bamba's residence in Mauritania is not well documented.  Bamba apparently moved around eastern Trarza, beginning with Souet-El-Ma, at the northeastern extremity of Lac Rkiz, where the French had a post.  He probably followed the movement of the Abyayri tents for a time, but grew tired of the transhumance pattern and settled in one or two places.  Bamba spent considerable time in reflection and writing.  He decided, in about 1905, to give the name Muridiyya to his approach to Islam, without rejecting the Qadiriyya influences which had shaped much of his search. His disciples came in considerable numbers to visit him. The complex logistics of these displacements and surveillance persuaded the administration to transfer his residence a third time - in 1907 to an isolated village in northern Senegal.

The joint project of the French and Baba had mixed results. The nature of the influence of the Sidiyya on Bamba is not clear. The “white” marabout was preoccupied with survival and orchestration of the colonial campaigns for the conquest of Mauritania; the news of Coppolani's assassination arrived while Bamba was in Trarza. It is said that Baba discouraged his “black” marabout client from any further pursuit of Tijaniyya affiliation. The four-year stay in Trarza certainly sealed bonds of friendship and respect between the two men and their respective entourages.  Baba's sons often visited the Murids in Baol, provided instruction to Bamba's children, and received the traditional gifts due to saintly and learned persons.  What is equally certain is that the stay convinced Bamba of the necessity, if not the virtue, of working within the colonial structures. By 1910 Bamba was willing to write exhortations to his followers to accept and take advantage of French rule, along the lines of Baba's own fatwa of 1903.  From Baba's perspective, Bamba's residence was at least as important: it gave the Sidiyya unparalleled access to the expanding Muridiyya networks in the Senegalese peanut basin, and an important source of revenue for years to come.

What is most striking about this Bamba episode is the enormous confidence which the French authorities placed in Sidiyya Baba. Only five years after his first visit to Saint-Louis, only a year after the beginning of active cooperation in Mauritania, at the very beginning of "pacification", the French were willing to entrust their ally with the custody of the marabout who posed the most serious problems for control of a vital part of the colonial economy: the newer peanut basin developing in eastern Cayor and Baol.  The colonial authorities were satisfied with the result, and they continued to seek Baba's advice about Muslim communities in Senegal.