On December 12, Washington and his men reached Fort Le Boeuf. Jacques Legardeur de Saint-Pierre succeeded Marin as commander of the French forces after Marin died on October 29, and he invited Washington to dine with him. Over dinner, Washington presented Saint-Pierre with the letter from Dinwiddie demanding an immediate French withdrawal from the Ohio Country. Saint-Pierre said, "As to the Summons you send me to retire, I do not think myself obliged to obey it." He told Washington that France's claim to the region was superior to that of the British, since René-Robert Cavelier, Sieur de La Salle had explored the Ohio Country nearly a century earlier. Washington's party left Fort Le Boeuf early on December 16 and arrived in Williamsburg on January 16, 1754. He stated in his report, "The French had swept south", detailing the steps which they had taken to fortify the area, and their intention to fortify the confluence of the Allegheny and Monongahela rivers. Even before Washington returned, Dinwiddie had sent a company of 40 men under William Trent to that point where they began construction of a small stockaded fort in the early months of 1754. Governor Duquesne sent additional French forces under Claude-Pierre Pécaudy de Contrecœur to relieve Saint-Pierre during the same period, and Contrecœur led 500 men south from Fort Venango on April 5, 1754. These forces arrived at the fort on April 16, but Contrecœur generously allowed Trent's small company to withdraw. He purchased their construction tools to continue building what became Fort Duquesne. Dinwiddie had ordered Washington to lead a larger force to assist Trent in his work, and Washington learned of Trent's retreat while he was en route. Mingo sachem Tanaghrisson had promised support to the British, so Washington continued toward Fort Duquesne and met with him. He then learned of a French scouting party in the area, so he combined Tanaghrisson's force with his own and surprised the "Canadiens" (French colonists of New France) on May 28 in what became known as the Battle of Jumonville Glen. They killed many of the Canadians, including their commanding officer Joseph Coulon de Jumonville, whose head was reportedly split open by Tanaghrisson with a tomahawk. Historian Fred Anderson suggests that Tanaghrisson was acting to gain the support of the British and to regain authority over his own people.