 Complete the following phrase:  The grenadiers of the 1st Battalion, now in the Armée des Ardennes, took part in on 23 May during the Battle of Hamptinne, Battle of Florenne, and Battle of Saint-Aubin. After the retreat of the Prussians, the whole of the 1st Battalion passed to the Army of the North Armée du Nord and contributed to the decisive Siege of Lille. It then served during the Flanders campaign and the 