  We present the metallicity results from the ARGOS spectroscopic survey of the
Galactic bulge. Our aim is to understand the formation of the Galactic bulge:
did it form via mergers, as expected from Lambda CDM theory, or from disk
instabilities, as suggested by its boxy/peanut shape, or both? We have obtained
spectra for 28,000 stars at a spectral resolution of R = 11,000. From these
spectra, we have determined stellar parameters and distances to an accuracy of
< 1.5 kpc. The stars in the inner Galaxy span a large range in [Fe/H], -2.8 <
[Fe/H] < +0.6. From the spatial distribution of the red clump stars as a
function of [Fe/H] (Ness et al. 2012a), we propose that the stars with [Fe/H] >
-0.5 are part of the boxy/peanut bar/bulge. We associate the lower metallicity
stars ([Fe/H] < -0.5) with the thick disk, which may be puffed up in the inner
region, and with the inner regions of the metal-weak thick disk and inner halo.
For the bulge stars with [Fe/H] > -0.5, we find two discrete populations; (i)
stars with [Fe/H] ~ -0.25 which provide a roughly constant fraction of the
stars in the latitude interval b = -5 deg to -10 deg, and (ii) a kinematically
colder, more metal-rich population with mean [Fe/H] ~ +0.15 which is more
prominent closer to the plane. The changing ratio of these components with
latitude appears as a vertical abundance gradient of the bulge. We attribute
both of these bulge components to instability-driven bar/bulge formation from
the thin disk. We do not exclude a weak underlying classical merger-generated
bulge component, but see no obvious kinematic association of any of our bulge
stars with such a classical bulge component. [abridged]
