The reionization of hydrogen and helium are intimately linked to the formation of the first galaxies and quasars, yet setting direct observational constraints on either process has proven to be highly challenging. Over the past few years, a variety of observations have started to shed light on both reionization events. I will review recent progress in the field, and discuss my group's work on metal enrichment by the first galaxies and on the thermal history of the intergalactic medium. These studies are providing unique insights into the first three billion years of evolution in the IGM, and will complement upcoming observations in developing a consensus picture of how and when hydrogen and helium were reionized.