John Montresor Captain John Montresor ( 22 April 1736 – 26 June 1799 ) was a British military engineer in North America . Early life . Born in Gibraltar 22 April 1736 to British military engineer James Gabriel Montresor and his first wife , Mary Haswell , John Montresor spent his early life there ( and presumably on Minorca , where his father was briefly stationed ) . He was in England between 1746 and 1750 , attending Westminster School . He learned the principles of engineering from his father , and in his later teens served as assistant engineer to his father at Gibraltar . French and Indian Wars . In 1754 , he accompanied his father to America , and served as an ensign in the 48th Regiment of Foot on the expedition to Fort Duquesne , also performing as a supernumerary engineer . In the defeat that followed he was wounded , but survived to learn of his promotion to lieutenant days before the battle . He remained in America , serving along the Mohawk River and at Fort Edward , then accompanying British forces to Halifax . In 1758 , he was commissioned a practicing engineer in the Corps of Engineers , and as such was present at the siege of Louisbourg , and later , at that of Quebec , there drawing one of the last known portraits of General Wolfe , who died in the deciding battle . With the defeat of the French , Montresor was sent to neighboring villages and as far afield as Cape Breton , using the language of his Huguenot ancestors to elicit oaths of allegiance . He was also twice sent overland from Quebec to Boston with dispatches , on one of these journeys , in a mid - winter blizzard , being reduced to eating belt and shoe leather in order to avoid starvation . He also , during this period , performed various surveys and prepared maps of Acadia , the Saint Lawrence River , and of his route along the Kennebec River . ( The journal of this last expedition through the wilds of Maine would fall into enemy hands in the American Revolution , and was used as a guide by Benedict Arnold in his expedition against Quebec . ) During Pontiac ' s Rebellion , he carried dispatches and led troops to besieged Fort Detroit . He designed and built fortifications on the Niagara River at Fort Niagara and Fort Erie as well as a series of blockhouses and an early gravity railroad along the Niagara Portage between 1762 and 1764 . Revolutionary - Era America . Stationed at Fort George ( the former site of Fort William Henry ) in 1765 , he witnessed rioting in Albany and New York City in response to the Stamp Act , and in the same year was promoted to captain lieutenant , and engineer extraordinary , as well as barrackmaster for ordnance in North America . Over the next several years , he surveyed the boundary between New York and New Jersey , and he repaired or constructed barracks and fortification s in Boston , New York City , the Bahamas , and Philadelphia , where he would build a fortification on Mud Island . During this period he also took a six - month leave in England , and spent time on Bermuda . He also purchased an island in New York Harbor which would be called Montresor ' s Island ( now Randall ' s Island ) . He was in Boston at the outset of the American Revolutionary War , and marched with Percy to relieve the British troops returning from Concord . He was appointed chief engineer in America and captain in late 1775 . He was present at the Battle of Long Island the next year , and was present at the execution of Nathan Hale on 22 September 1776 . It is said that he kindly sheltered Hale in his office , giving him pen and paper to write final letters to his family , and that the execution moved him deeply . He was sent to the rebel lines under flag of truce to report the event , and he conveyed Hale ' s last words to William Hull . Having been superseded as chief engineer , he was placed as aide - de - camp on the staff of General William Howe , but was later reinstated as chief engineer . On 13 January 1777 his home on Montresor ' s Island was burned . In 1777 he was involved in the military campaigns in New Jersey , and present at the action at Quibbleton . He also participated at Brandywine later that year , and accompanied the army to Philadelphia where he launched the attack that destroyed his own Mud Island defences . He directed the construction of new defences for the city , and along with John André , he was one of the planners of the lavish ball , the " Mischianza " , given in Philadelphia in honor of General Howe . Again superseded in his role as chief engineer , he returned to England and , in March 1779 resigned from the army , bringing to an end over two decades of American service , all reported in journals ( although many of these were lost ) . Retirement and death . In England , he was called before Parliament to testify on the conduct of the war , and on several occasions required to support his expenditures during his various campaigns ( for which he is said to have been imprisoned at one point ) . He purchased an estate at Belmont , Kent , had a residence at Portland Place , London , and he served as director of the French Hospital . He toured Europe in 1785 and 1786 , visiting France , Germany and Switzerland . In his later years , his accounts came under scrutiny , and much of his property was seized by the state to recover disallowed expenses . He died in Maidstone prison , where he was incarcerated apparently in connection with his outstanding debts , on 26 June 1799 . Family . Montresor ' s romantic life has been the subject of much writing . He married at New York 1 March 1764 , Frances Tucker , who was born in New York , 23 April 1744 , daughter of Thomas Tucker of Bermuda , stepdaughter of Reverend Samuel Auchmuty and half - sister of General Sir Samuel Auchmuty . She returned to England with her husband , and survived him , dying 28 June 1828 , at Rose Hill , Kent . By her , he had , with others , General Sir Henry Tucker Montresor , General Sir Thomas Gage Montresor , and Mary Lucy Montresor , who became the first wife of General Sir Frederick William Mulcaster ( half - brother of Capt Sir William Howe Mulcaster ) . In addition to these relationships , he also had other more irregular connections . A surviving letter from Detroit , 1763 , mentions the death of an apparent mistress , " poor Nancy " , and that he had been " on the Common " since . Likewise , he made a small grant for the support of the child of the daughter of a local English farmer , of which John was the father . Finally , his name appears broadly as the father of Frances , second wife of Ethan Allen . Born to a Mohawk Valley woman on ( Ethan Allen would later record ) 4 April 1760 , Frances was adopted by her mother ' s later companion , Crean Brush , one - time secretary of the Assembly of the Colony of New York . As to her paternity , when her daughter Frances " Fanny " Allen entered Hôtel - Dieu in 1808 , her mother ' s maiden name was recorded as Montresor . Her tombstone names her Montezuma , while an 1858 history written using family information calls her Frances Montuzan , relating that her father was a British colonel killed in the French and Indian War . Popular opinion makes John Montresor the father of Frances . This has not been in small part due to his role in a popular best - selling novel of the time . Fiction . John Montresor has gained a certain notoriety beyond his historical role due to the writings of his first - cousin Susanna Haswell Rowson . One of the main characters in her popular novel " Charlotte Temple " , named John Montraville , was based , at least in part , on Montresor . In the sequel , " Lucy Temple , Charlotte ' s Daughter " , Montraville is even said to have lived at Portland Place , once Montresor ' s residence . In the original novel , Montraville seduces the title character , an innocent English schoolgirl , and induces her to run away to America . He then abandons her , destitute and pregnant , to die in childbirth . Some authors have taken this to be a verbatim account of an event in Montresor ' s life , with only the name changed ( the author subtitles the work , " A Tale of Truth " ) , while others see in it a fictionalized account of the circumstances surrounding the birth of the future Frances Allen . However , the tale also bears strong similarity to one told of General John Burgoyne , and it seems likely that the author had broader inspiration for her tale .