Wide bandgap group III nitride semiconductors are currently experiencing the most exciting development. Within a very short period of some five years, high-brightness blue and green light-emitting diodes (LEDs) have been commercialized, and ultra violet (UV) and blue laser diodes (LDs), high-frequency transistors (TRs) and UV detectors, which will be able to operate at high temperatures, have been demonstrated. In this paper, renaissance and progress in heteroepitaxial growth of group III nitride semiconductors on highly mismatched substrates in the last quarter century are reviewed as the groundwork for recently developed high-performance devices based on nitrides. Recent advances in crystal growth will be also discussed.