Henry Leonard d ' Arendt Henry Leonard Philipe , Baron d ' Arendt was a Prussian officer who volunteered to serve in the Continental Army during the American Revolutionary War . He was made colonel of the German Battalion in March 1777 and remained its commander until the unit was disbanded at the beginning of 1781 . He was placed in charge during the Siege of Fort Mifflin in October 1777 but did not distinguish himself , allowing Samuel Smith and Simeon Thayer to exercise actual command of the besieged fort . D ' Arendt was the one who first suggested that George Washington appoint an Inspector General to his staff . This advice proved to be very useful to the American cause . Career . An officer from the Kingdom of Prussia , D ' Arendt arrived in America as a volunteer to fight with the army of George Washington . He was described as " a very military - looking man , six - feet high and elegantly formed " . He was appointed colonel of the German Battalion on 19 March 1777 . The previous commander , Nicholas Haussegger defected to the British earlier in the year . D ' Arendt remained the German Battalion ' s commander until it was disbanded on 1 January 1781 . On 23 September 1777 , George Washington ordered d ' Arendt to assume command of Fort Mifflin . However , he did not come to the fort for four weeks due to illness . Evidently , the Prussian was confused because there were two men named Greene under his authority . On 20 October , Washington tried to straighten out the problem in a letter . Sir : I am just now favoured with yours of this date , and am sorry that you laboured under any mistake on account of there being two Officers of the name of Green . Colo . Christopher Greene of Rhode Island is to command at Red Bank , and Lt . Colo . John Greene of Virginia is to go into Fort Mifflin with the detachment under his command . I have no Blank Commissions with me and am therefore obliged to send you a certificate of your Rank and date of your Appointment . I beg you will make the greatest haste to throw yourself into Fort Mifflin ; in the defence of which I wish you the greatest success . I am etc . When d ' Arendt finally arrived on 21 October , he was taken on a tour of inspection by Smith and Major François - Louis Teissèdre de Fleury . When they reached the damaged northwest blockhouse , the Prussian asked what had happened . They told him that it was often a target of British fire and that a store of ammunition had been blown up the day before . To their amazement and disgust , d ' Arendt leapt through two windows in his haste to flee the blockhouse . Fleury turned to Smith and exclaimed , " Par Dieu ! C ' est un poltroon ! " ( By God , he ' s a coward . ) Smith responded that they should scare the Prussian away from the fort before he caused problems . Smith soon applied to Washington to be relieved of his post . The American commander - in - chief diplomatically reminded Smith that d ' Arendt was in charge and told him he could do as he wished , but that he hoped that he would make the right choice . Smith stayed . D ' Arendt was still unwell , so Lieutenant Colonel Samuel Smith continued to exercise control over the garrison and its operations during the Siege of Fort Mifflin . When Smith was wounded , it was Major Simeon Thayer who took command of the fort , not d ' Arendt . D ' Arendt was the officer who recommended to Washington that an Inspector General be included on his staff . A council of war agreed with this idea . It was seen as a way to utilize the military knowledge of foreign officers . In December 1777 , the Continental Congress formalized the rank and appointed Thomas Conway to the office . The inspectors , whose duties were to teach the soldiers how to manoeuver according to the best European standards , were ordered to report directly to Congress . Conway soon proved a poor choice because he became embroiled in the Conway Cabal and a dispute over rank . He sent his resignation to Congress and it was accepted on 28 April 1778 , much to Conway ' s surprise . Meanwhile , Washington appointed Friedrich Wilhelm von Steuben as a temporary inspector general on 28 March 1778 . Steuben proved a happy choice and Washington strenuously pressed for his promotion to Major General , which Congress approved on 5 May 1778 . When the German Battalion fought at the Battle of Monmouth on 28 June 1778 , evidently d ' Arendt was not present because its acting commander was Lieutenant Colonel Ludowick Weltner .