Short answers, pulled from the story.
Gebhard Leberecht von Blücher was a Prussian field marshal born on the 16th of December 1742 in Rostock. He is best known for commanding Prussian forces at the Battle of Leipzig in 1813 and for the decisive intervention of his army at the Battle of Waterloo in 1815, which ended Napoleon's final campaign. His soldiers nicknamed him Marschall Vorwärts, meaning Marshal Forward, for his relentlessly aggressive style of warfare.
Blücher commanded the Prussian Army of the Lower Rhine at Waterloo on the 18th of June 1815. After being injured and temporarily pinned under his dead horse at the Battle of Ligny two days earlier, he led his army on a night march along muddy paths and arrived on the battlefield in the late afternoon. His vanguard drew off Napoleon's reserves while his troops pushed the Old Guard back at Plancenoit, helping Wellington's forces overcome the Middle Guard and secure a decisive Allied victory.
Frederick the Great effectively dismissed Blücher in 1773 after Blücher submitted a rude letter of resignation following his being passed over for promotion. Frederick's reply was blunt: "Captain Blücher can take himself to the devil." Blücher spent the years until Frederick's death in 1786 working as a farmer before being reinstated as a major in his old regiment, the Red Hussars.
George Stephenson, the pioneering British locomotive engineer, named one of his early locomotives Blücher in gratitude for the field marshal's service. The small mining village near Stephenson's birthplace in Wylam also carries the name Blucher in his honour.
Blücher died at Krieblowitz on the 12th of September 1819 and was interred in a mausoleum built on those grounds. When Soviet forces took Krieblowitz in 1945, soldiers broke into the mausoleum and scattered his remains. After 1989, a Polish priest collected some of the remains and interred them in the catacomb of the church in Sośnica, three kilometres from the now-Polish village of Krobielowice.
Blücher and Paul von Hindenburg are the only Prussian-German military officers to have been awarded the Star of the Grand Cross of the Iron Cross. Together they rank as the most highly decorated Prussian-German soldiers in history.