This article examines the effect of emerging vernaculars on the social diffusion and cultural roles of standardization projects in multi-dialectal migrant communities. I explore the impact of Standard Q'eqchi', a standard variety crafted by language activists, on Lowland Q'eqchi', a new vernacular variety of Q'eqchi' Mayan spoken in migrant rural communities in northwestern and northern Guatemala. Rather than being innovations, the sociolinguistic history of highland migrants backgrounds the social meanings associated with both varieties. The enregisterment of Lowland Q'eqchi' and Standard Q'eqchi' occurred concurrently in the lowlands, reinforcing and enabling each other. I discuss the congruent articulation of successful standardization projects with emerging local regimes of social indexicality and the way ethnic ideologies and their linguistic expression mediate changes in cultural representations of ethnicity, authority and education among the Q'eqchi' Maya. [Language ideologies, dialectology, Q'eqchi', Mayan languages, Mesoamerica]