1st American Regiment ( 1783 – 1784 ) 1st American Regiment , also known as Jackson ' s Continental Regiment of 1783 - 1784 , was the last unit in the Continental Army , retained after the close of the American Revolutionary War . This regiment , under the command of Colonel Henry Jackson of Massachusetts , was not the same unit as Jackson ' s Additional Continental Regiment of 1777 , which had become the 16th Massachusetts Regiment in 1780 and had been disbanded in 1781 . Equally , this regiment should not be confused with the First American Regiment of 1784 - 1791 , which was originally commanded by Colonel Josiah Harmar , has remained in service to the present , and is now the 3d United States Infantry Regiment ( The Old Guard ) . However , when Jackson ' s Regiment was disbanded in 1784 one company remained in service and was assigned to Harmar ' s Regiment . The remaining company , under Captain John Doughty , had been raised by Alexander Hamilton in 1776 and had ended the war as the 2d Company , 2nd Continental Artillery Regiment . Through various reorganizations the company has continued in the United States Army to the present day . Peacetime regular army . The ratification of the Treaty of Paris , September 3 , 1783 , presented the Continental Congress with the question of providing the newly independent United States with a peacetime Regular Army . Congress considered several plans for a permanent peace establishment , but failed to adopt any of them . A compromise was found when the Congress finally settled on the expedient of provisionally organizing a single regiment to remain in service . Command of the new regiment was given to Colonel Henry Jackson . Organization . Jackson ' s Regiment was authorized as an element of the Continental Army on October 23 , 1783 . Under this arrangement the regiment and the Continental Army were virtually the same thing . It was organized at West Point , New York , on November 3 , 1783 . The field units which had composed the Continental Army were disbanded in November 1783 , and Jackson ' s Regiment was the force which succeeded them . His regiment was to consist of a regimental headquarters and nine companies . Most , but not all , of the men under his command were veterans of the Massachusetts Line . In addition to the Massachusetts veterans , Captain John Doughty ' s Company of the 2nd Continental Artillery Regiment was attached to the regiment , as were the remaining officers and men of the Corps of Invalids . The 2nd Continental Artillery had been placed on the New York quota in 1781 and the Corps of Invalids had been raised at large . Doughty ' s Artillery Company . Doughty ' s Company was originally authorized on January 6 , 1776 by the New York Provincial Congress as the New York Provincial Artillery Company . The company was organized at New York City in the spring of 1776 . Its first commander was Captain Alexander Hamilton . On March 17 , 1777 the company , then commanded by Captain John Doughty , was assigned to Lamb ' s Continental Artillery Regiment . In August 1779 it was numbered the 2nd Company in the 2nd Continental Artillery Regiment . Corps of Invalids . On June 20 , 1777 the Continental Congress resolved to raise a Corps of Invalids . The Invalids , a body of physically disabled Continental Army veterans , were organized as a regiment of eight companies under the command of Colonel Lewis Nicola . They were intended to serve as guards at magazines , hospitals , and similar establishments . It was also hoped that the corps could serve as a military school , but this seems not to have happened . Strength of the 1st American Regiment , January 3 , 1784 . On January 3 , 1784 the Commanding General of the Army , Major General Henry Knox , submitted to Congress a list of Continental Army officers remaining in service , and a return showing the organization of Jackson ' s Regiment . The regiment consisted of 775 officers and men : Service history . The First American Regiment served in garrison at West Point , New York until its disbandment . When the British Army evacuated New York City as a result of negotiations between George Washington and Sir Guy Carleton , Colonel Jackson had immediate command of the 800 - man column that marched into New York City on November 25 , 1783 , under General Washington , to formally take possession of the city for the United States . Disbandment of the Regiment . On June 2 , 1784 , Congress resolved : Alexander Hamilton Battery . Captain Doughty received the brevet rank of major on September 30 , 1783 . He was the major of artillery appearing in the return submitted by General Knox . The Congressional resolve of June 2 , 1784 caused Major Doughty ' s Artillery Company to continue in service , as his company was the unit retained . To his company belongs the distinction of being the only element of the Continental Army to continue in service after the war as an element of the United States Army . On the following day , June 3 , 1784 the Continental Congress resolved to raise a new regiment , the First American Regiment of 1784 - 1791 , consisting of eight infantry companies and two artillery companies . Captain Doughty furnished the senior company . The 2d Artillery Company , First American Regiment , was raised in Pennsylvania and commanded by Captain Thomas Douglass , who had been an officer in Thomas Proctor ' s 4th Continental Artillery Regiment from 1777 to 1783 . The organization of the United States Army changed frequently in the late eighteenth and early nineteenth century ; but on June 1 , 1821 the company that had been commanded by Major Doughty in 1784 was designated Company " F , " 4th United States Regiment of Artillery . The company retained this designation until 1901 . The company received a different designation in that year and , in a further reorganization on May 31 , 1907 it became Battery " D , " 5th United States Field Artillery Regiment . The battery served in France in World War I as an element of the 1st Division , American Expeditionary Forces . On October 1 , 1940 the battery became Battery " D , " 5th Field Artillery Battalion . It served in North Africa and Europe in World War II . After a further period of reorganization , the unit was redesignated the 1st Rocket Howitzer Battalion , 5th Artillery , on April 20 , 1960 and as the 1st Battalion , 5th Artillery ( Alexander Hamilton Battery ) , on January 20 , 1964 .