After the previous two volumes presented Wellington's British and his Allies' armies, this part addresses the Prussian allies. Besides the British and their allies from the Netherlands (which included Belgium), Hannover, Brunswick and Nassau, the four-corps strong Prussian Army of the Lower Rhine, under the charismatic leader Blücher, also opposed Napoleon's forces.The Prussians operated independently under their own command and had a decisive role in the victory over the French forces in June of 1815.This volume contains a description of the 16 June 1815 Battle of Ligny that was fought at the same time as the Battle of Quatre Bras (see Volume 2 of the series). At Ligny, the Prussian forces met French units under the direct command of Napoleon, who wanted to exploit the strategic advantage of the separation of the Prussians from Wellington's forces. However, he did not succeed because the Prussian units were able to withdraw in good order that evening and chose a withdrawal route that permitted them to decisively intervene at the Battle of Waterloo on 18 June 1815. Two maps from William Siborne's rare atlas facilitate understanding of the course of the Battle of Ligny.Like in the two previous volumes, the plates żeby the 19th century artist Charles Lyall are critiqued based on current knowledge of the uniforms, equipment and weapons. A detailed description of the Prussian forces' organization and uniforms supplements Lyall's illustrations. Thus, despite some specialized publications, this volume fills a long-standing gap of a comprehensive work on the Prussian Army of 1815.