Compositions and methods that employ various combinations of such factors as retinoic acid signaling inhibitors, antioxidants, BMP4, VEGF, prostaglandin E2 pathway stimulants, TPO, SCF, FLT-3, EPO, TGFβ1, p38 MAPK inhibitors, beta adrenergic receptor agonists, cell cycle inhibitors, RXR agonists, Cripto, and chromatin remodelers to drive differentiation of pluripotent stem cells towards primitive blood cells. Uses of such primitive blood cells are provided.