Regret (1) I stumbled onto this belatedly and (2) the sidetrack
Nevertheless, Fuchs, to clarify: Both sides made ample use of Montagnards. We even had a name for the ones on the other side: "VCM." Their collaboration and guidance (literally) were essential to allowing NVA units to pop up "out of nowhere," as it were--on the coastal plain in northen Binh Dinh....

A couple of the main ethnic groups from which US recruited, the Rhade and Jarai, were easy to attract because they feared and hated lowland Vietnamese---whether communist or GVN....and had formed FULRO, their own independence "Front." They saw an association with the US as a counterbalance to the hated ARVN. Their anti-Vietnamese sentiment did not play entirely into US hands, as they also sought strength from a noted, local, anti-Viet force--namely, the Khmer Rouge.....An interesting side note is the fact that Khmer Rouge leader Pol Pot's personal guard unit was, from the '60's until his end, composed solely of Jarai.

Cheers,
Mike.