Final answer:
Before Valley Forge, the war had been difficult for Washington and the Americans with setbacks such as the loss of Philadelphia and high desertions, but Washington's victory at Trenton provided a much-needed morale boost.
Step-by-step explanation:
Before the American forces camped at Valley Forge, the war had been quite challenging for General Washington and his troops. The British had secured significant victories, capturing Philadelphia after defeating Washington's soldiers at the Battle of Brandywine Creek, which was a critical loss for the Americans as it was where the Continental Congress met. Despite the hardship, there was a notable triumph for Washington's victory at Trenton, which boosted morale significantly when it was most needed. Washington's leadership during these difficult times before Valley Forge was marked by strategic retreats and evasion of complete defeat, with his tactical withdrawal from Long Island serving as an example of his ability to preserve the army under adverse conditions.
Valley Forge, however, marked a low point with severe shortages of supplies, rampant disease, and high desertion rates that threatened the integrity and morale of the American army. These challenges highlighted the resilience and determination of Washington and his troops in the face of dire adversity.