Montgomery Blair Montgomery Blair ( May 10 , 1813 – July 27 , 1883 ) , the son of Francis Preston Blair , elder brother of Francis Preston Blair , Jr . and cousin of B . Gratz Brown , was a politician and lawyer from Maryland . Despite belonging to a prominent slaveholding family , Blair was an abolitionist and a loyal member of the Cabinet of Abraham Lincoln during the American Civil War . Life and career . Blair was born in Franklin County , Kentucky . His father , Francis P . Blair , Sr . , was , as editor of the " Washington Globe " , a prominent figure in the Democratic Party during the Jacksonian era , and as a boy Montgomery " often listened to the talk of his father and Andrew Jackson . " Blair graduated from the United States Military Academy in 1835 , but after a year ' s service in the Seminole War , he left the Army , studied law , and began practice at St Louis , Missouri . After serving as United States district attorney ( 1839 – 43 ) and as judge of the court of common pleas ( 1834 – 1849 ) , he moved to Maryland in 1852 and devoted himself to law practice principally in the United States Supreme Court . He was United States Solicitor in the Court of Claims ( 1855 – 58 ) and was associated with George T . Curtis as counsel for the plaintiff in the " Dred Scott v . Sandford " case of 1857 . The Blairs , like many other nationalist Democrats , but unusually for politicians from the border states , had abandoned the Democratic Party in the wake of the Kansas - Nebraska Act and had been among the founding leaders of the new Republican Party . In 1860 Montgomery Blair took an active part in the presidential campaign on behalf of Abraham Lincoln . After his election , Lincoln invited Blair to be part of his cabinet as Postmaster - General . Lincoln expected Blair , who advocated taking a firm stance with the southern states , to help balance more conciliatory members of his cabinet . Blair served as Postmaster - General from 1861 until September 1864 , when Lincoln accepted an earlier offer by Blair to resign . Lincoln ' s action may have been a response to the hostility of the Radical Republican faction , who stipulated that Blair ' s retirement should follow the withdrawal of John C . Frémont ' s name as a candidate for the presidential nomination in that year . Regarding Lincoln ' s action , Blair told his wife that the president had acted " from the best motives " and that " it is for the best all around . " After he left the cabinet , Blair still campaigned for Lincoln ' s re - election and Lincoln and the Blair family retained close ties . Under Blair ' s administration , such reforms and improvements as the establishment of free city delivery , the adoption of a money order system , and the use of railway mail cars were instituted — the last having been suggested by George B . Armstrong ( d . 1871 ) , of Chicago , who from 1869 until his death was general superintendent of the United States railway mail service . Differing from the Republican Party on the Reconstruction policy , Blair gave his adherence to the Democratic Party after the Civil War , along with his brother , who was the Democratic vice presidential candidate in 1868 . His manor in present - day Silver Spring , Maryland was named Falkland . It was burned by Confederate troops during their thrust towards Washington , D . C . He died at Silver Spring and was buried at Rock Creek Cemetery . Montgomery Blair ' s wife was Mary Woodbury , a daughter of Levi Woodbury . Together , they were the great - grandparents of actor Montgomery Clift . Blair was portrayed by actor Lew Temple in the movie Saving Lincoln ( 2012 ) . In the 2012 film , Lincoln , Blair is portrayed by the actor , Byron Jennings . Honors . Montgomery Blair High School in Silver Spring , Maryland .