Battle of the Clouds

The Battle of the Clouds (also known as the Battle of Warren, Battle of Whitehorse Tavern, or the Battle of Goshen) was an aborted engagement of the Philadelphia campaign of the American Revolutionary War on September 16, 1777, in the area surrounding present day Malvern, Pennsylvania. After the American defeat at the Battle of Brandywine, the British Army remained encamped near Chadds Ford. When British commander William Howe was informed that the weakened American force was less than ten miles (16 km) away, he decided to press for another decisive victory.

George Washington learned of Howe's plans, and prepared for battle. Before the two armies could fully engage, a torrential downpour ensued. Significantly outnumbered, and with tens of thousands of cartridges ruined by the rain, Washington opted for a tactical retreat. Bogged down by rain and mud, the British allowed Washington and his army to withdraw.

Background
After Washington's defeat at the Battle of Brandywine, he was intent on accomplishing two tasks. He wanted to protect Philadelphia from British forces under the command of Howe, and he needed to replenish the rapidly dwindling supplies and munitions which were stored in Reading, Pennsylvania. Washington withdrew across the Schuylkill River, marched through Philadelphia, and headed northwest. Since the Schuylkill was fordable only far upstream starting at Matson's Ford (present-day Conshohocken), Washington could protect both the capital and the vital supply areas to the west from behind the river barrier. Yet he reconsidered, and recrossed the river to face the British, who had moved little since Brandywine, owing to a shortage of wagons to carry both their wounded and their baggage.

Battle
General Howe was alerted that Washington had recrossed the Schuylkill on the afternoon of September 15, and by midnight, his troops were on the march toward the major road junction where the White Horse Tavern stood. The going was difficult, because the weather had been rainy and windy, and the troops and wagons turned the roads into muddy quagmires. The next morning, Washington's 10,000 man army was moving west through the Great Valley, bound by the North and South Valley Hills on either side. He learned from his cavalry that the British were advancing on him from the south just a few miles away. Although moving to the North Valley Hills would have given Washington more time to deploy and possibly fortify, he ordered the army south directly toward the enemy to take up a defensive position on the South Valley Hills. The position was three miles (5 km) long and was strong, especially in the center.

Washington sent an advance force under General Anthony Wayne to slow the British progress. At about 2:00 pm, his men encountered the advance jäger units of the Hessian column on one road. These forces began skirmishing, and the Americans very nearly captured Colonel Carl von Donop when he became separated from his main column with a small company of jägers. The main British column, led by General Charles Cornwallis, met with Wayne's Pennsylvania militia on another road at around 3:00, who gave way in a panicked retreat, suffering 10 killed or wounded.

While this went on, Washington, who was trying to organize the line of battle, had a change of heart about the position, and ended up withdrawing the army north of the tavern. This withdrawal was just getting underway when it began pouring rain. Hessian jäger captain Johann Ewald described it as "an extraordinary thunderstorm, [...] combined with the heaviest downpour in this world." The British army halted its advance, although General Wilhelm von Knyphausen ordered the jägers to engage the enemy. Ewald and his men rushed forward, swords drawn since their muskets were inoperable due to wet powder, and capture 34 men. Ewald reported losing 5 killed, 7 wounded, and 3 captured in this action. The storm, which historian Thomas McGuire describes as "a classic nor'easter", raged well into the next day. The British were forced to construct a makeshift camp (having left their tents behind that day), and Washington managed to form a battle line, but a great deal of his ammunition was spoiled by the rain and poorly-constructed cartridge boxes.

Aftermath
Washington once again withdrew beyond the Schuylkill on September 19 to cover both the capital and his supply area, but he left behind General Wayne's Pennsylvania division of 1,500 men and four guns with orders to harass the British rear. Howe's army found it nearly impossible to follow Washington over the rutted, muddy roads. The decision was made to wait out the storm, then move toward their objective.

Wayne was to be joined by militia, and together they were to strike at the enemy baggage train as the British advanced on Washington's main army. However his force was surprised at the Battle of Paoli, and the British were free to occupy Philadelphia.