The American forces had to retreat since they were being attacked by the Hessians. They need to come up with a plan because it was winter and their men had little supplies.
Killing the Hessians at the Guard House
They reached the river after Washington came up with the idea of crossing it with boats. They were tired from walking many hours. They planned to cross at 8pm.
Americans Surprise the Hessians in Their Homes
Washington originally wanted to attack at night but he later realised that they wouldn't make it in time. It also didn't help that they were being shot at by Hessians.
General Gall Dies From his Injuries
After marching even more they reached the guard house, and they had to deal with the 6 guards. Luckily they were sleeping and just getting ready.
The battle of Trenton took place the day after Christmas so the Americans could have a leg up on the Hessians. The Hessians were drinking and partying the day before so they were in no shape to fight back.
During the battle many shots were fired, and one of those shot hit General Gall it the chest. After that happened the Hessians were almost forced to surrender.