For nearly nineteen years after his arrival in Mexico, Junipero was engaged in active missionary work, mainly among the Indians of the Sierra Gorda, whom he successfully instructed in the first principles of the Catholic faith and in the simpler arts of peace. Then came his selection as general head, or president, of the Missions of California, the charge of which, on the expulsion of the Jesuits, in 1768, had passed over to the Franciscans. These, thirteen in number, were all in Lower California, for no attempt had as yet been made to evangelize the upper province. This, however, the indefatigable apostle was now to undertake by co-operating with Jose de Galvez in his proposed northwest expedition [1]. Junipero was now fifty-five years of age, and could look back upon a career of effort and accomplishment which to any less active man might well seem to have earned repose for body and mind. Yet great as his services to church and civilization had been in the past, by far the most important part of his life-work still lay before him.
As a result of the conference between Galvez and Father Junipero, it was decided that their joint expedition should be sent out in two portions--one by sea and one by land; the land portion being again sub-divided into two, in imitation, Palou informs us, of the policy of the patriarch Joseph, "so that if one came to misfortune, the other might still be saved." It was arranged that four missionaries should go into the ships, and one with the advance-detachment of the land-force, the second part of which was to include the president himself. So far as the work of the missionaries was concerned their immediate purpose was to establish three settlements--one at San Diego, a second at Monterey, and a third on a site to be selected, about midway between the two, which was to be called San Buenaventura. The two divisions of the land-force were under the leadership of Captain Fernando Rivera y Moncada and Governor Portolà respectively. The ships were to carry all the heavier portions of the camp equipage, provisions, household goods, vestments and sacred vessels; the land-parties were to take with them herds and flocks from Loreto. The understanding was that whichever party first reached San Diego was to wait there twenty days for the rest, and in the event of their failure to arrive within that time, to push on to Monterey.