 One attempt to alleviate these difficulties failed when nearly 1,000 men were killed or captured at the August 16 Battle of Bennington.Furthermore, news reached Burgoyne on August 28 that St. Leger's expedition down the Mohawk River valley had turned back after the failed Siege of Fort Stanwix.General William Howe had taken his army from New York City by sea on a campaign to capture Philadelphia instead of moving north to meet Burgoyne.