John French vs Prince Rupert of the Rhine

French's BEF fought its first major engagement at the Battle of Mons. The British forces held off the German advance but were forced to retreat, beginning the 'Great Retreat' to the Marne.

French commanded the BEF during the First Battle of Ypres, which halted the German advance in Flanders. The battle resulted in heavy casualties and the beginning of trench warfare.

John French was appointed the first commander of the British Expeditionary Force (BEF) at the outbreak of World War I. He led the BEF during the early battles of the war.

French was replaced as commander of the BEF by General Douglas Haig after the Battle of Loos. His leadership was criticized for poor communication and tactical failures.

Prince Rupert commanded the Royalist cavalry at the Battle of Edgehill, the first major battle of the English Civil War. His cavalry charge was initially successful but failed to achieve a decisive victory, as the battle ended inconclusively.

Prince Rupert led Royalist forces at the Battle of Marston Moor, where they were decisively defeated by the Parliamentarian and Scottish armies. The loss cost the Royalists control of northern England and marked a turning point in the war.

Prince Rupert commanded the Royalist cavalry at the Battle of Naseby, the final major battle of the First English Civil War. The Royalist army was destroyed, and Rupert's reputation as a commander was severely damaged.