Short answers, pulled from the story.
Allied cavalry under Wintzingerode and Tettenborn engaged French forces near Saint-Dizier to cover Napoleon's retreat toward Paris. The battle involved Cossacks, Hussars, and horse artillery attempting to cut off French troops crossing the Marne river.
Wintzingerode led the main Allied cavalry force while Tettenborn commanded the advance guard consisting of five regiments of Cossacks and one regiment of Hussars. These commanders coordinated attacks against French divisions occupying villages along the road near Vitry.
Skirmishing began on the evening of the 24th of March 1814 when Allies caught up with French infantry at Thieblemont. Major engagements continued through the early morning of the 26th of March 1814 before Allied forces retreated toward Vitry.
The battlefield stretched across flat country cut by vineyards and hedges which prevented Allied cavalry from using its numerical superiority effectively. Woods and low bottoms hemmed the area preventing even one regiment of Cossacks from operating advantageously.
Tettenborn maintained his contest despite great personal danger and suffered a total loss of only forty men. His unit included about 1,000 horses divided into four squadrons of Hussars and remaining Cossacks.