In the planning for the Wilmington attack the term barrage is used several times. The term at that time was bombardment. The barrage as a tactic was developed in the 1880s by the British, and the first English military usage of the term was in WWI at the battle of Neuve Chapelle.
William Bilbo mentions that Lincoln's face is on the 50-cent piece. Lincoln appeared on the 50-cent fractional currency piece (paper currency that was issued instead of silver coins during the Civil War), but not until the fourth series, which started in 1869.
Shortly after Thaddeus Stevens tell the full House that he's not for racial equality, he walks outside into the rotunda area and sits down. He is quickly joined by an angry fellow Representative. The shot of him sitting on a bench in the rotunda shows a modern electrical outlet in the wall below him.
Early in the movie there is a military band playing. There is a clarinetist who's using a modern Boehm-fingering clarinet. Until the 1930s or so clarinets were made with the Albert fingering keys. The curved register key is the Albert giveaway, which is not seen in the band's clarinet.
Filming took place in the Virginia State Capitol. On the wall behind the Speaker of the House is an inscribed marble tablet which reads: "Erected by THE SOCIETY OF THE COLONIAL DAMES OF AMERICA IN THE STATE OF VIRGINIA 1916". Additionally, the society itself was not formed until 1890.
During a scene after one of the House sessions, the camera pans to the Washington statue in the Virginia Presidents room at the Virginia State Capitol. Shots from the front include the bust to the right, President Woodrow Wilson, who was born in 1856.
At the beginning of the film, a young soldier tells Lincoln that he'd heard Lincoln deliver the Gettysburg Address two years earlier. The scene is set in December 1864 or early January 1865. Lincoln delivered the Gettysburg Address on November 19, 1863, 13 months earlier.
In the opening scene, as the soldiers start to disperse and return to their units, the shot from behind Lincoln shows Private Green turning and throwing his gun around his shoulder. In the next scene, shot from behind Private Green, he turns and throws the gun around his shoulder again.
When Grant and Lincoln are talking at the house during Lincoln's visit to Petersburg, they both stand up, Lincoln extends his hand to shake Grant's hand, and Grant takes it. In the next shot, Lincoln extends his hand and Grant takes it again.
When Robert waits outside the military hospital, the shot from inside the hospital shows the American flag over the door billowing in a breeze. In the next shot, from outside, the flag is completely still.
When President Lincoln is speaking to Private Green and Corporal Clark, shots from behind the soldiers show a hard rain falling, with water dripping off Clark's hat every few seconds. Shots from in front of the two soldiers shows very little rain, and no water drips from Clark's hat.
When Lincoln and Tad are going to the military hospital in the carriage, Lincoln clearly puts the papers he is working on in a folder on his left. In the next shot, the papers are back in his lap, and he puts them in the briefcase.
Throughout the speech by Lincoln to his cabinet which begins with him slamming the table and saying, "I can't listen to this anymore..." Seward (David Straitharn) rests his clasped hands under his chin. As Lincoln says "...with the fate of human dignity in our hands" Seward lowers his hands from his chin. In the very next shot, as Lincoln shouts "Now! Now! Now!", Seward's hands are once again clasped under his chin resulting in a "jump cut."
When General Grant's staff emerges from Appomattox Courthouse, Ely Parker is behind Grant and stands with his hands crossed in front of him. In the next shot, Grant starts descending the stairs to greet Robert Edward Lee, and Parker emerges from inside the courthouse crossing his hands.
During the debate on the day before the vote is taken, Lincoln's team has to rush back to the White House to secure a letter from Lincoln which will reassure the house that he has not met with Confederate commissioners. The team members are seen running out of the Front of the Capitol to do this. But the Capitol was built the wrong way round and, in reality, they would have rushed out the back to get to the White House faster.
In Lincoln's death scene, he is shown lying somewhat on his side, on top of the covers on a bed at the Petersen House (across from Ford's Theatre). In actuality, he lingered nearly ten hours and had been put into bed under the covers to keep him warm, and diagonally, because he was so tall he wouldn't have fit otherwise.
Abraham Lincoln was known to be very offended by profanity, going so far as to sternly rebuke generals in the field for cursing in his presence. While his 'Ethan Allen' joke can be considered a bawdy attempt to soften the mood in a tense situation and the profanity he uses when chastising his cabinet can be chalked up to extreme frustration, it is highly unlikely that he would have tolerated Preston Blair cursing in front of young Tad Lincoln, as he does in the movie. Though Blair's daughter rebukes the old man, the President seems unaffected by it.
The two-seat horse buggy ridden by Lincoln had two men in the front, but they're in the wrong places. The shotgun rider should be on the right, and the coachman, with the whip, should be on the left, to protect pedestrians from the whip.
When the Speaker of the House does the Congressional roll call, in alphabetical order by state, he starts with Connecticut. He should've started with California, which was admitted to the union in 1850 and had 3 representatives in the 38th congress (March 1863 to March 1865).
In 1863, Secretary of War Edwin Stanton "commissioned" Tad Lincoln an artillery 2nd lieutenant. In the film, Tad wears the uniform of an infantry lieutenant colonel, outranking his brother, Captain Robert Lincoln, by two grades.
In many of the scenes set in the House of Representatives, the marble behind the Speaker bears the words "State of Virginia." All of the House scenes were filmed in the Old Chamber at the Virginia State Capitol, in Richmond, Va.
Raymond H. Johnson plays Republican Congressman John F. McKenzie, but the end credits list a different actor. Raymond H. Johnson is listed in the End Credits as Raymond Johnson, under House of Representatives.
In the scene where Lincoln is speaking with Ms. Keckley on the North Portico, columns can be seen along the north facing wall of the White House to Lincoln's left. The White House has never had columns along this wall.
During the House of Representatives voting for the Thirteenth Amendment January 31, 1865, Ulysses S. Grant was shown wearing the four star rank of a General. At the time, he was a three star Lieuenant General. Official records show that he did not attain the rank of a four star General until 25 July 1866.
Thaddeus Stevens (Tommy Lee Jones) says that the 13th amendment will be the first time slavery is mentioned in the Constitution. Slavery is often believed to be mentioned explicitly - particularly in the first paragraph of Article 1, Section 9 - but it was not. In fact, the absence of the direct mention of slavery formed the basis of an argument made by abolitionists including Lysander Spooner that slavery was unconstitutional even before the 13th amendment.
Lincoln's secretary, John Nicolay, was Bavarian by birth, but immigrated with his parents to the United States at age 6, grew up in Cincinnati, Ohio, and would not have spoken with a German accent. (Despite this, in the 1992 documentary Lincoln (1992), he was voiced by future California Governor Arnold Schwarzenegger with his usual trademark Germanic accent.)
Early in the film, Lincoln meets with Seward and others in a White House office or drawing room, and bright daylight streams through a window in the background. The camera briefly pans past a clock that reads 5 pm, very close to sunset in mid-November.
The goof item below may give away important plot points.
Incorrectly regarded as goofs
During the show at the end, the pit orchestra plays Beethoven's "Egmont" Overture. The scene is a play (not a concert) attended by Tad Lincoln that night at Grover's Theater: "Aladdin! Or His Wonderful Lamp."