Hendrik George, Count de Perponcher Sedlnitsky (also Sedlnitzky; 19 May 1771 – 29 November 1856) was a Dutch general and diplomat.

[2] When Prince Frederik died on 6 January 1799 in Padua during an Austrian campaign in Italy, Perponcher transferred his allegiance to the British.

After that campaign ended he resigned his British commission under threat of forfeiture of his Dutch possessions by Napoleon I of France, who annexed the Netherlands in 1810 and frowned on his new subjects serving in hostile armies.

He led the campaign against the retreating French, and besieged the fortresses of Gorinchem, Bergen op Zoom, and Antwerp in late 1813 and early 1814.

After the First Peace of Paris in 1814 he was for the first time appointed Dutch minister plenipotentiary at the Prussian court in Berlin.

When Saxe-Weimar received orders from the Duke of Wellington to evacuate the strategic crossroads at Quatre Bras, he alerted Perponcher, because he thought that could not be right, and Perponcher took the matter up with major-general Jean Victor de Constant Rebecque, the chief-of-staff of the Netherlands Mobile Army.

[4] The two brigades together (though far outnumbered) managed to hold off the onslaught of the French left wing under Marshal Michel Ney long enough the next day to allow Wellington to bring up British reinforcements.

Others credit Perponcher with giving the order to move the brigade to a safer position before the initial French bombardment started around noon on 18 June.

After the Battle of Waterloo Perponcher was right away returned to his post as Dutch envoy to the Prussian Court in Berlin.