Viruses have been recognized as abundant but virtually unknown members of the soil microbiome. Here we will explore early results in the burgeoning field of soil viral community ecology as we begin to understand viral diversity, biogeography, and impacts on microbial ecology and biogeochemical cycling in terrestrial ecosystems. Using shotgun viral metagenomic (viromic) approaches to recover and sequence the viral size fraction, tens of thousands of ‘species-level’ viral populations have been recovered from a wide range of soils, consistently indicating substantial viral diversity across terrestrial ecosystems. Soil viral communities are often strongly spatially structured, even over short distances, and they exhibit reproducible successional patterns following wetting of dry soil. Soil moisture appears to correlate strongly with viral community composition, with a bloom of viral particles and substantial increase in viral diversity following the first annual rains in seasonally dry Mediterranean grasslands. These early insights into soil viral ecology suggest that viruses likely play a substantial role in bacterial mortality, biogeochemical cycling, and food web dynamics in both natural and managed terrestrial ecosystems.