  We investigate the stellar populations in the star forming ring of the
luminous infrared galaxy NGC 7469. We use Hubble Space Telescope
multi-wavelength (UV through NIR) imaging complemented with new K-band
ground-based long-slit spectroscopy, and mid-IR and radio maps. Spectral energy
distributions (SEDs) and evolutionary synthesis models have been used to
characterize the star formation at different scales from those of individual
star clusters (tens of pc) to that of the entire star-forming ring (kpc scale).
At the smallest scales two different populations of massive (1-10 x 10^6 Msun)
clusters are identified. About 25% of the clusters are young (1-3 Myr) and
extincted (A_V ~ 3 mag), whereas the vast majority are of intermediate age (~9
to 20 Myr) and less obscured (A_V ~ 1 mag). At larger (hundreds of pc) scale,
an analysis of the integrated SED and spectroscopic data of the ring indicates
the presence of two stellar populations. The young (5-6 Myr) and obscured
stellar population accounts for the Br_gamma emission and most of the IR
luminosity, and about one-third of the stellar mass of the ring. The much less
obscured intermediate-age population has properties similar to those of the
majority of the (older) 1.1um-selected star clusters. These two populations are
spatially anti-correlated. The UV-optical-NIR continuum (including the majority
of the clusters) of the ring traces mostly the mildly obscured intermediate-age
population, while the MIR and radio peaks mark the location of the youngest and
obscured star-forming regions. This study emphasizes the need for
multi-wavelength, high-angular resolution observations to characterize the star
formation in the dust-obscured regions commonly present in LIRGs.
