On April 27, 1763, Obwandiyag, an Odawa also called Pontiac, assembled a council of warriors from various tribes near this site and urged them to fight to maintain control of their land and way of life. For more than a century, tribes in the Ohio Valley and the Great Lakes had allied with different European nations competing for dominance there, and most favored the French, who were trading partners and not very numerous, over the British, whose policies and rapidly growing population threatened Indian existence. After the French lost the Seven Years' War in 1763, the tribes faced a single European power, Britain and its colonies, and resistance began almost immediately with attacks on posts and forts. The council included members of the Odawa, Potawatomi, Wyandot, Huron, and Ojibwa bands, and Pontiac told of Delaware prophet Neolin's vision of resisting the British and returning to traditional ways. The plan that followed, to surprise and seize Fort Detroit on May 7, 1763, became a siege lasting nearly six months and involving more than 900 Great Lakes warriors. That summer thirteen other British posts were attacked, and at Detroit, on July 31, the British attempt to engage the Indians failed disastrously at Bloody Run. In October, when the French declined to provide support, warriors returned home to their families, the siege ended, and the tribes' fight for their homelands and rights continued.