Which preposition to use with recruitment

of Occurrences 6%

The duke of Parma, daily breaking down under the progress of disease, and agitated by these reverses, repaired again to Spa, taking at once every possible means for the recruitment of his army and the recovery of his health, on which its discipline and the chances of success now so evidently depended.

in Occurrences 1%

Nothing on the face of the act or in its public history indicated that the British Government proposed to attempt recruitment in the United States, nor did it ever give intimation of such intention to this Government.

Which preposition to use with  recruitment