Philip Henson Philip Henson ( December 28 , 1827 - January 10 , 1911 ) was a scout and spy for the Union Army during the American Civil War . Upon the election of U . S . Grant to the U . S . Presidency ( 1869 – 1877 ) , Henson became the " first Special " Secret Service Agent of the United States of America , serving until Grant ' s death in 1885 . During the course of his life and careers , Phillip Henson would interact with such famous 19th century persons as abolitionist John Brown , Cherokee Chiefs John Ross a . k . a . Kooweskoowe and Stand Watie a . k . a . Degataga , Tennessee and Texas Governor Sam Houston , actor John Wilkes Booth , Confederate Postmaster General John Henninger Reagan , Confederate Secretary of State Judah Philip Benjamin , U . S . Congressman from Illinois Elihu Benjamin Washburne , Union General and Transcontinental Railroad executive Grenville Mellen Dodge , New York political boss William Marcy Tweed , U . S . Congressional Medal of Honor recipient First Lieutenant " Nineveh Shaw McKeen " ( 1837 – 1890 ) , and the ancestors of 20th century Hollywood legend Cecil B . DeMille . History . Henson was born in Blount Springs , Alabama . At an early age he would accompany his father , a Federal Indian Agent , on his travels to Kansas , Mississippi , Oklahoma , Tennessee , and Texas . Upon his father ' s death in 1839 , Henson , at twelve ( 12 ) years of age , left home to work as a mail carrier for U . S . Government contractor Daniel Seavers , a herder for Edwards and Cornelius , and an overseer for Thomas Turnbow in order to help support his widowed mother and siblings . He would not return home until 1859 after leading a settlement expedition to the Mesilla Valley ( now New Mexico ) where he earned the rank of Captain which was conferred upon him by the grateful company of settlers . On the eve of the American Civil War , Henson was working as a storekeeper and living with his wife Celestine Rachel in Corinth , Mississippi . Just as he was about to have to work once again as an overseer for planter Moore McCauley in order that he ' d be exempt from serving in the Confederate army , Alabama Governor A . B . Moore and Montgomery Mayor A . J . Noble appointed him Captain of the State ' s Militia and the Confederacy ' s Postmaster General , John Henninger Reagan selected him for the position of Field Supervisor in the Confederate Post Office Department . As a result , he resumed traveling throughout the Southwest . During the course of his travels he revisited former Texas Governor Houston , who ' d been removed from office upon his refusal to take an oath of loyalty to the Confederacy . Houston presented Henson with a life changing proposition : become a scout and spy for the Union . He was sent by Houston to Illinois to meet with U . S . Congressman Washburne and a little known Union Colonel named Grant who was " killing time " drilling and recruiting Illinois Volunteers . Henson swore an oath of loyalty to the Union , because , as he ' d attest to whenever asked about it , " " I believed in it " " . Thus began a twenty five year relationship between the two men that would see them move together from Civil War battlefields to the White House . Career as a Scout and Spy during the Civil War . Henson ' s career as a Union scout and spy commenced in earnest when he had a fateful meeting with Confederate General Leonidas Polk , who was known as " The Fighting Bishop " due to the fact that before the war Polk was the Episcopalian Bishop of Louisiana . Polk informed Henson that Confederate Generals Gideon Johnson Pillow and John Buchanan Floyd were in command of Fort Henry and Fort Donelson , respectively . Henson in turn advised Grant of Polk ' s admission that two " political " Generals were in charge of defending the two key forts . Shortly thereafter , Grant would earn his nickname nickname " Unconditional Surrender " when he recorded the first two victories of the war for the Union as a result of his taking advantage of the inferior skill sets of both Pillow and Floyd to win the Battles of Forts Henry and Donelson in 1862 . Unfortunately for both Henson and Grant , the war made its way to Corinth which prevented Henson from warning Grant in advance about the " surprise attack " Confederate Generals Albert Sidney Johnston and P . G . T . Beauregard planned for him at Pittsburg Landing , Tennessee . The resulting bloodbath would become known as the Battle of Shiloh , and Grant would find himself with an unwanted nickname , " The Butcher " . It was after Shiloh , when Grant , Generals William Tecumseh Sherman , Grenville Mellen Dodge , and Colonel John Aaron Rawlins finally arrived in a by then evacuated Corinth , during a meeting with Henson in attendance , that the subject of a scorched earth policy and the topic of total war was first discussed . Also , at this time , Henson in response to requests from Andrew Jackson Hamilton and Charles Christopher Sheats would introduce the Southern Unionists known as " The Mossbacks of Nickajack " to Grant , resulting in the enlistment of over 2 , 000 loyal Alabamans in the legendary " 1st Alabama Cavalry US Volunteers " . Later on during the war , they ' d be accorded the honor by General Sherman of serving as his escort during his March to the Sea . The following year Henson made his way to Vicksburg , Mississippi to gather information on the Confederate forces in the city . Much to Grant ' s good fortune he managed to convince Confederate General John C . Pemberton ( the CSA commander of the city ) to take him into his confidence . Henson gave Pemberton misinformation in regards to the purported inhumane treatment Confederate prisoners of war were supposedly receiving from their Union captors . Pemberton then had him share his story with the troops within Vicksburg in the hope of " stirring the Southern soul " which in turn gave him free run of the entire city . The information he garnered , including details about the city ' s canals , was ultimately utilized by Grant in the successful siege and subsequent surrender of Vicksburg in 1863 which would further Grant ' s celebrity as the " thinking man ' s General " . A year later in 1864 , Henson had the misfortune of being brought to the attention of Confederate General Nathan Bedford Forrest too many times for his own good . Forrest arrested and imprisoned him for over six months until Henson finally managed to escape and return to Union lines prior to the surrender of Confederate General Robert E . Lee to Grant at Appomattox . It was then that his " handler " General Dodge was quoted as having said to Henson " " Well , Phil , the damn rope has not been made yet to hang you " " . Dodge referred to Henson as his " most colorful spy " . Afterwards , when Forrest was asked about his not having " " hung him until dead " , " he uttered that Henson was " " The most dangerous spy operating within the Confederacy " . " However , it wouldn ' t be until much later that Henson in an interview with one of Joseph Pulitzer ' s " Fighting Editors " George Sibley Johns in September 1887 would himself say about his efforts on behalf and to the benefit of his beloved country ; " " I don ' t know how , but I believe that God was with me and preserved me for what I had to do . I never felt a fear of death . When I was ordered to be shot once , I told my wife that I did not believe that I would be shot , but if I should be I was ready to die for the cause , as my work would be finished " . " For his contributions to the war effort Henson would receive brevets for the rank of Major . Career as " Special " Secret Service Agent and Death . For Henson , especially taking into consideration his skills and talents as a master of disguise and dialects , impersonator , horseman , marksman , sharpshooter and cryptographer , his career as a " Special " Secret Service Agent was a natural progression for him . In the aftermath of the assassination of Abraham Lincoln , General Grant asked him to conduct a " confidential and discrete " investigation to discover any and all details of Lincoln ' s death . It was a task that continued during Grant ' s Presidency and resulted in brevets for the rank of Lieutenant Colonel being bestowed upon him . Ultimately , it took over twenty years to complete . According to Henson ' s sons , he told them Grant had died without giving permission to release the findings , but that " " Damn thing of it was to track the trail of blood , bodies and bucks ' til it got me there " . " Henson died in Paris , Texas at the home of his eldest son , Phillip Edgar , a well - known cotton dealer , at 10 : 15 P . M . on Tuesday evening the 10th day of January , 1911 . The younger son Captain William O ' Dell resided in San Antonio , Texas at the time . Phillip Henson and his wife , Celestine , who had died approximately ten years before him , are interred side by side in the Henry Cemetery in Corinth , Mississippi . According to his sons his last words were " " Reckon you never ever know until you get there " " .