After the Battle of the Cowshed in Chapter 4, the animals in Animal Farm celebrate their victory by having a spontaneous celebration in which they sing "Beasts of England" and run the flag up the flagpole. The sheep who was felled in the battle is also given a funeral.
They then establish two rituals. First, they create a military honor called "Animal Hero, First Class," which they give to Snowball and Boxer. The decoration, which the honorees wear on Sundays and holidays, is a brass medal the animals had discovered in the harness room. The sheep who was killed in battle receives the distinction of "Animal Hero, Second Class." Second, they find Mr. Jones's gun and place it at the foot of the flagpole and decide to fire it twice a year to commemorate the Battle of the Cowshed (on October 12) and to mark the anniversary of the Rebellion (on Midsummer Day). These honors are reminiscent of the way in which the Soviets marked military victories.
After the battle, they hold a ceremony to honor the military heroes. Snowball and boxer are given medals for their courage and victory. A sheep is honored posthumously for his effort, and given a medal.
They also use the gun to shoot , much like a fireworks display, and decide to do this every year on the anniversary of this battle, and of their rebellion.