What day in December did Napoleon complete what is considered his greatest victory ?
Whilst he himself moved on Laon , but when an incredulous Ney and Mortier saw the greater part of the Army of Silesia lying before them , Napoleon 's illusions were crushed for Blucher had drew his army of 85,000 troops and 150 guns in a very strong position south of LaonAt 3:00 am on the morning of 9 March under cover of a thick blizzard , the Battle of Laon began as Napoleon audaciously threw his infantry forward and stormed Etouvelles .