Battle of Quatre Bras
Summary
The same day as Ligny, Ney attempted to take the strategic crossroads of Quatre Bras to prevent junction between Wellington's and Blücher's armies. Despite vigorous initial attack and temporary capture of the crossroads, Ney failed to exploit advantage and was repulsed by allied reinforcements. The battle ended without clear victor, but the Allies retained the position.
Historical context
Napoleon had divided his forces to strike the Prussians at Ligny and the British at Quatre Bras separately. Ney, charged with blocking Wellington, hesitated and did not immediately commit all his troops, notably d'Erlon's corps, which wandered between the two battlefields. This indecision allowed the Allies to resist then counterattack with reinforcements from Brussels.
Tactics
The French attacked in line along the Charleroi road with Kellermann's cavalry and Reille's infantry. Artillery bombarded hedges and allied positions. Fighting was fierce around Gemincourt farm and Bossu wood. Hanoverian and Dutch reinforcements stabilized the allied line. Ney, without coordination with Napoleon, finally withdrew in good order.
Consequences
The battle prevented Ney from cutting the Namur road and reinforcing Napoleon at Ligny. By evening the Anglo-Dutch held the field. Two days later this resistance allowed Wellington to choose the Waterloo ground and Blücher to return in support. Ney's failure at Quatre Bras was a key factor in the strategic French failure of the campaign.