After Napoleon escaped from Elba in February 1815 he entered Paris on 20 March. In the face of a European coalition his strategy depended on attacking before the enemy could launch a combined assault. He aimed to destroy the British and Prussian forces under Wellington and Blücher on the northern frontier, before attacking the Austrians and Russians under Prince Schwarzenberg who were gathering in the east. To this effect, he positioned himself near Charleroi between Blücher and Wellington to prevent them joining forces. On 12 June he seized Charleroi, whilst the allies still believed he was in Paris, and defeated Blücher at Ligny on 16 June. Assuming, wrongly, that the Prussians were retreating towards their base in Namur, Napoleon sent a detachment under Grouchy to pursue them. Meanwhile, at Quatre Bras, Marshal Ney was facing Wellington. Napoleon joined Ney's forces and although Wellington was in fact victorious, he was compelled to retreat toward Brussels. South of Waterloo, Wellington took up a strong position between Mont-Saint-Jean and Belle-Alliance and awaited attack. This picture depicts the dawn of 18 June before the final battle of the Waterloo campaign, with Napoleon surrounded by his troops. About noon that day, Napoleon launched a massive attack against the British centre. The Prussians arrived later in the day having eluded Grouchy by marching on Wavre instead of Namur. Their arrival proved the turning point of the battle and the French retreated. Napoleon left the field and signed his second abdication on 22 June.