Integrated cellulosic ethanol and corn ethanol production processes reduce the capital and operating costs of cellulosic ethanol production through high levels of integration with pre-existing corn ethanol processing equipment. The processes comprise separating corn starch from other, non-fermentable corn components (e.g. germ, protein, fiber, etc.) and cofermenting sugars derived from the corn starch in the presence of a pretreated cellulose feed. The cofermentation can be carried out using one or more hemicellulose sugar utilizing yeast strains, for example, such as one or more yeast strains.