The paper develops a method to interpret faint galaxy data by focusing on the integrated light radiated from the galaxy population as a whole. The authors model the emission history of the universe at ultraviolet, optical, and near-infrared wavelengths from the present epoch to $z \approx 4$ by tracing the evolution of the galaxy luminosity density, determined from deep spectroscopic samples and the *Hubble Deep Field* (HDF) imaging survey. They find that the global spectrophotometric properties of field galaxies can be well fit by a simple stellar evolution model defined by a time-dependent star formation rate (SFR) per unit comoving volume and a universal initial mass function (IMF) extending from 0.1 to 125 $M_{\odot}$. The best-fit models show a sharp rise in the global SFR from a redshift of zero to a peak value at $z \approx 1.5$, followed by a decline at higher redshifts. The models predict a stellar mass density at the present epoch of $\Omega_{\star} h_{50}^2 \gtrsim 0.005$, consistent with observed values in nearby galaxies. The models also account for the entire background light recorded in the galaxy counts down to very faint magnitudes probed by the HDF. The study suggests that only about 20% of the current stellar content of galaxies was produced at $z > 2$, indicating a low cosmic metallicity at early times, which is consistent with the observed enrichment history of damped Lyman-$\alpha$ systems. The biggest uncertainty is the amount of starlight absorbed by dust and reradiated in the IR at early epochs. A "monolithic collapse" model, where half of the present-day stars formed at $z > 2.5$ and were shrouded by dust, can be consistent with the global history of light but overpredicts the metal mass density at high redshifts.The paper develops a method to interpret faint galaxy data by focusing on the integrated light radiated from the galaxy population as a whole. The authors model the emission history of the universe at ultraviolet, optical, and near-infrared wavelengths from the present epoch to $z \approx 4$ by tracing the evolution of the galaxy luminosity density, determined from deep spectroscopic samples and the *Hubble Deep Field* (HDF) imaging survey. They find that the global spectrophotometric properties of field galaxies can be well fit by a simple stellar evolution model defined by a time-dependent star formation rate (SFR) per unit comoving volume and a universal initial mass function (IMF) extending from 0.1 to 125 $M_{\odot}$. The best-fit models show a sharp rise in the global SFR from a redshift of zero to a peak value at $z \approx 1.5$, followed by a decline at higher redshifts. The models predict a stellar mass density at the present epoch of $\Omega_{\star} h_{50}^2 \gtrsim 0.005$, consistent with observed values in nearby galaxies. The models also account for the entire background light recorded in the galaxy counts down to very faint magnitudes probed by the HDF. The study suggests that only about 20% of the current stellar content of galaxies was produced at $z > 2$, indicating a low cosmic metallicity at early times, which is consistent with the observed enrichment history of damped Lyman-$\alpha$ systems. The biggest uncertainty is the amount of starlight absorbed by dust and reradiated in the IR at early epochs. A "monolithic collapse" model, where half of the present-day stars formed at $z > 2.5$ and were shrouded by dust, can be consistent with the global history of light but overpredicts the metal mass density at high redshifts.