In 1622, the Second Anglo-Powhatan War erupted. Its origins are disputed. English apologists for the company say that Opchanacanough initiated the war. Robert Williams, a 21st-century Native American law professor, argues that Opchanacanough had secured concessions from Governor Yeardley which the company would not accept. Thus, Opchanacanough's attack, on 18 April 1622, may have been a pre-emptive attempt to defeat the colony before reinforcements arrived.