We present and discuss the results of a search for extremely metal-poor stars based on photometry from data release DR1.1 of the SkyMapper imaging survey of the southern sky. In particular, we outline our photometric selection procedures and describe the low-resolution (R~3000) spectroscopic follow-up observations that are used to provide estimates of effective temperature, surface gravity, and metallicity ([Fe/H]) for the candidates. The selection process is very efficient: of the 2618 candidates with low-resolution spectra that have photometric metallicity estimates less than or equal to -2.0, 41 per cent have [Fe/H]=-2.0dex. The most metal-poor candidate in the sample has [Fe/H]<-4.75 and is notably carbon rich. Except at the lowest metallicities ([Fe/H]<-4), the stars observed spectroscopically are dominated by a 'carbon-normal' population with [C/Fe]1D,LTE=7.3 (predominantly CEMP-s) while any bias against stars with A(C)1D,LTE+1 (predominantly CEMP-no) is not readily quantifiable given the uncertainty in the SkyMapper v-band DR1.1 photometry. We find that the metallicity distribution function of the observed sample has a power-law slope of {Delta}(LogN)/{Delta}[Fe/H]=1.5+/-0.1dex per dex for -4.0=<[Fe/H]=<-2.75, but appears to drop abruptly at [Fe/H]~-4.2, in line with previous studies.

Cone search capability for table J/MNRAS/489/5900/table1 (Comparison of [Fe/H]fitter values with those from high-dispersion spectroscopy literature values)

Cone search capability for table J/MNRAS/489/5900/table2 (Details of the derived parameters for the observed stars with [Fe/H]fitter<-3.0)

Cone search capability for table J/MNRAS/489/5900/table3 (Details of the derived parameters for additional candidates with [Fe/H]fitter<-3.0)