George S . Greene George Sears " Pop " Greene ( May 6 , 1801 – January 28 , 1899 ) was a civil engineer and a Union general during the American Civil War . He was part of the Greene family of Rhode Island , which had a distinguished military record for the United States . His greatest contribution during the war was his defense of the Union right flank at Culp ' s Hill during the Battle of Gettysburg . As a civilian , he was a founder of the American Society of Civil Engineers and Architects and was responsible for numerous railroads and aqueduct construction projects in the northeastern United States . Early life . Greene was born in Apponaug , Rhode Island , one of nine children of Caleb and Sarah Robinson ( Greene ) Greene . His family had roots in the founding of Rhode Island and in the American Revolutionary War , including General Nathanael Greene , George ' s second cousin . Caleb was a financially shrewd ship owner and merchant , but the Embargo Act of 1807 , which prohibited U . S . vessels from carrying goods to other countries , and the War of 1812 left his family in financial difficulties . Young George attended Wrentham Academy and then a Latin grammar school in Providence and hoped to attend Brown University there , but his impoverished father could not afford it , so he moved to New York City and found work in a dry goods store on Pearl Street . In the New York store , Greene met Major Sylvanus Thayer , superintendent of the United States Military Academy , who recommended him to the Secretary of War for appointment to the academy . Greene entered West Point at age 18 and graduated second of 35 cadets in the class of 1823 . ( Classmates of Greene ' s included future Union Adjutant General Lorenzo Thomas , Joseph K . Mansfield , David Hunter , Dennis Hart Mahan , and Albert Sidney Johnston . ) Top graduates of the academy generally chose the Engineers as their branch , but Greene decided on the artillery and was commissioned a second lieutenant in the 3rd U . S . Artillery Regiment . However , due to his excellent academic performance , he stayed at the academy until 1827 as an assistant professor of mathematics and as a principal assistant professor of engineering . One of the students he taught during this period was Cadet Robert E . Lee . In the summer of 1828 Greene married Mary Elizabeth Vinton , sister of his best friend at West Point , David Vinton . Elizabeth gave birth to three children over the next four years : Mary Vinton , George Sears , and Francis Vinton Greene . While assigned to Fort Sullivan in Eastport , Maine in 1833 , tragedy struck Greene ' s family : Elizabeth and all three of their children died within seven months , probably from tuberculosis . To ease the pain on his mind and to escape the isolation and loneliness of peacetime Army garrison duty , he immersed himself in study of both the law and medicine , coming close to professional certification in both by the time he resigned his commission in 1836 to become a civil engineer . Greene built railroads in six states and designed municipal sewage and water systems for Washington , D . C . , Detroit , and several other cities . In New York City , he designed the Croton Aqueduct reservoir in Central Park and the enlarged High Bridge over the Harlem River . He was one of twelve founders in New York City of the American Society of Civil Engineers and Architects . While on a trip to Maine for railroad surveying , he met Martha Barrett Dana , daughter of Samuel Dana , a prominent Massachusetts politician . They were married in Charlestown , Massachusetts , on February 21 , 1837 . They had six children together , including four sons ( three of them later served in the military ) , one daughter , and one son who died in infancy . Civil War . Despite being over 60 years old and having been out of the Army for 25 years , the crisis of the Union compelled Greene to seek to rejoin the service . He was essentially apolitical and was not an abolitionist , but he was a firm believer in restoring the Union . He was appointed colonel of the 60th New York Infantry regiment on January 18 , 1862 . The regiment of upstate New Yorkers had been dissatisfied with their colonel and the company commanders had petitioned for his removal . Governor Edwin D . Morgan , although initially reluctant to appoint Greene because of his age , saw his 13 years of regular army experience as a solution to his political / military problem . During this period , Governor John A . Andrew of Massachusetts was also prepared to offer Greene a regiment , but Greene chose to serve New York . The officers of the 60th were dismayed when the elderly , gray - haired man reported for duty . They had requested that their lieutenant colonel be promoted , which would have raised many of them in rank themselves . On April 28 , 1862 , Greene was appointed brigadier general of volunteers and served on the staff of Maj . Gen . Nathaniel Banks in the Shenandoah Valley campaign against Stonewall Jackson . At age 61 , Greene was one of the oldest generals in the Union army and his troops took to calling him " Old Man " or " Pap " Greene . ( There were actually 17 general officers in the Civil War older than Greene . ) However , his age did not keep him from being one of the most aggressive commanders in the army . He commanded the 3rd Brigade , 2nd Division , II Corps , of the Army of Virginia at the Battle of Cedar Mountain during the Northern Virginia Campaign . Attacked by a Confederate force three times the size of his own , Greene and his men refused to give ground , holding out until the neighboring Union units were forced to withdraw . His division commander , Brig . Gen . John W . Geary , received a severe wound during the action and Greene took command of the division temporarily . Greene was again temporarily elevated to command of his division , now designated part of the XII Corps of the Army of the Potomac , at the Battle of Antietam . His division ' s three brigades were led by junior officers who had survived Cedar Mountain . Even though XII Corps commander Brig . Gen . Joseph K . Mansfield was killed shortly after the fighting began , Greene led a crushing attack against the Confederates near the Dunker Church , achieving the farthest penetration of Maj . Gen . Stonewall Jackson ' s lines than any Union unit . Under immense pressure , Greene held his small division ( only 1 , 727 men engaged at the start of the day ) in advance of the rest of the Army for four hours , but eventually withdrew after suffering heavy losses . While the division was posted to Harpers Ferry , Greene took a three - week sick leave . Maj . Gen . Oliver O . Howard speculated that Greene , like many of his fellow officers , was sickened by the stench of dead and wounded at Antietam . When he returned , there was a new division commander , Brig . Gen . Geary . Greene was disgruntled that Geary , with only a few days seniority over him , was selected for the post ; Geary had been wounded at Cedar Mountain and his combat record was not as good , but his political connections and a sentiment that a wounded officer should not be set back in his career unnecessarily , gave him the nod . Greene resumed command of the 3rd Brigade , which was involved in minor skirmishes in northern Virginia and not engaged at the Battle of Fredericksburg in December . At the Battle of Chancellorsville in May 1863 , his brigade was in the center of the line . When the Union right — the XI Corps — collapsed , Greene ' s brigade was subjected to enfilade artillery fire and then infantry assaults . He had ordered his men to fortify their positions 200 yards to their front using abatis and trenches and they were able to hold out against several Confederate assaults , although losing 528 men of 2 , 032 engaged . During part of the battle , Greene once again assumed temporary command of the division when Geary was wounded again . Gettysburg . The Battle of Gettysburg was the highlight of Greene ' s military career . On July 2 , 1863 , Maj . Gen . George G . Meade shifted almost the entire XII Corps from the Union right to strengthen the left flank , which was under heavy attack . Greene ' s lone brigade of 1 , 350 New Yorkers ( five regiments ) was left to defend a one - half - mile line on Culp ' s Hill when an entire Confederate division attacked . Fortunately , Greene had previously demonstrated good sense ( as befits a civil engineer ) by insisting that his troops construct strong field fortifications , despite a lack of interest in doing so from his division commander , Geary , and corps commander , Maj . Gen . Henry W . Slocum . In Greene ' s finest moment of the war , his preparations proved decisive and his brigade held off multiple attacks for hours . He was active the entire engagement rallying his men to defend their positions in the darkness . Brig . Gen . Alpheus Williams , acting corps commander on July 2 , commended Greene for his " skill and judgment " in this defense , especially in his using the " advantages " of his position . Late at night , the rest of the XII Corps returned to Culp ' s Hill . The fighting resumed the next morning and raged for over seven hours , but the Union troops held Culp ' s Hill . They regained some of the lost ground and thwarted renewed Confederate attacks . The battle for Culp ' s Hill included the two oldest generals in each army , Greene at 62 and Brig . Gen . William " Extra Billy " Smith at 65 . The desperate fighting on the Union right flank was as important as the more famous defense of the Union left flank on July 2 , by Col . Strong Vincent ' s brigade on Little Round Top . In fact , given that the Union line was only 400 yards from the vital Union supply line on the Baltimore Pike , it can be argued that it was more important . However , Greene ' s contribution to this critical battle have never been widely heralded , principally because of a dispute between Meade and Slocum over the filing of their official reports . But a member of Greene ' s brigade wrote : Western Theater . In the fall of 1863 , the XII Corps was transferred to the West to reinforce the Union forces besieged at Chattanooga . At the Battle of Wauhatchie , during a surprise night attack by the Confederate forces , Greene was wounded in the face , with his jaw crushed and some teeth carried away . Subsequent surgery was not able to correct his condition and he suffered from the effects of his wound for the rest of his life . After six weeks of medical leave , he was assigned to light court - martial duty until January 1865 , when he was sent to join Maj . Gen . William T . Sherman ' s army in North Carolina . Initially Greene voluntarily served on the staff of Maj . Gen . Jacob D . Cox participating in the battle at Kinston , where he had his horse shot out from under him . At the very end of the war Greene was in command of the 3rd Brigade in Absalom Baird ' s 3rd Division , XIV Corps , and participated in the capture of Raleigh and the pursuit of Gen . Joseph E . Johnston ' s army until its surrender . Postbellum career . After the war , Greene served on court - martial duty for a year and then returned to civil engineering in New York and Washington , D . C . From 1867 to 1871 he was the chief engineer commissioner of the Croton Aqueduct Department in New York . At the age of 86 , he inspected the entire 30 - mile Croton Aqueduct structure on foot . He served as president of the American Society of Civil Engineers from 1875 to 1877 and president of the New York Genealogical and Biographical Society . He was appointed to West Point ' s Board of Visitors in 1881 . By 1892 , Greene was the oldest surviving Union general and the oldest living graduate of West Point . He petitioned the United States Congress for an engineer captain ' s pension that would be of help to his family after his death . The best that Congress was willing to do was arranged by Congressman and Gettysburg veteran Daniel E . Sickles of New York , a first lieutenant ' s pension , based on the highest rank Greene had achieved in the regular army . On August 18 , 1894 , Greene took the oath of office as a first lieutenant of artillery and became , at 93 , the oldest lieutenant in the U . S . Army for 48 hours . Veterans in MOLLUS declared that he was the oldest lieutenant in world history . Legacy . Greene died at age 97 in Morristown , New Jersey , and was buried in the Greene family cemetery in Warwick , Rhode Island , with a two - ton boulder from Culp ' s Hill placed above his grave . He is memorialized with a statue erected in 1906 by the State of New York on Culp ' s Hill in Gettysburg National Military Park . Greene ' s wife Martha died in 1883 at an age of 74 . Their oldest son , Lieutenant Samuel Dana Greene , was the executive officer on the ironclad ship USS " Monitor " during the famous Battle of Hampton Roads . Another of their sons , Francis V . Greene , commanded a brigade at the Battle of Manila during the Spanish - American War . A third , Charles Thurston Greene , was a lieutenant on his father ' s staff at Culp ' s Hill . Later in 1863 , Charles was wounded by an artillery shell and his leg was amputated , but he remained on active service until 1870 . George Sears Greene , Jr . , volunteered to serve but was not allowed to do so by his father so he could survive and carry on the family name . A description of George Sears Greene from Lt . George K . Collins of the 149th New York Infantry sums up the general :