Nearly every American knows that John Wilkes Booth murdered President Abraham Lincoln at Ford’s Theater on April 14, 1865. Seeking to avenge the South for the Confederacy’s imminent defeat in the Civil War, Booth crept into the presidential box, shot Lincoln in the head, and leapt to the stage to make his escape. Lincoln never regained consciousness and died about nine hours later.

Was Abraham Lincoln the only casualty that night? First Lady Mary Lincoln, seated next to her husband when he was shot, experienced bouts of manic depression and erratic behavior after her husband’s murder. But the Lincolns were not alone in the presidential box that night. They invited several different couples to attend that evening’s performance of Our American Cousin, but all declined in favor of others plans. Finally, U.S. Army Major Henry Rathbone and his fiancée, Clara Harris, accepted the invitation to see the play with President and Mrs. Lincoln. It was a decision that would haunt them both for the rest of their lives. They became John Wilkes Booth’s victims just as surely as if Booth had shot them along with the President.

Henry Rathbone had seen combat at Fredericksburg and Antietam before taking a Washington, D.C. staff job in the war’s later days. Clara Harris was the daughter of U.S. Senator Ira Harris of New York. Harris’s first wife had died young, and around 1848 he married a widow named Pauline Rathbone. Harris brought one son and three daughters, including Clara, to his second marriage. His new wife had two sons, Henry and Jared. For about seventeen years before that fateful night at Ford’s Theater, Henry Rathbone and Clara Harris had been step-siblings. Around 1863, they were engaged to be married.

Clara Harris became friendly with Mary Lincoln during the war and regularly attended the opera and theater with the First Lady. On April 14, 1865, after General and Mrs. Ulysses S. Grant politely declined the Lincolns’ invitation to Ford’s Theater, Mrs. Lincoln asked Clara Harris and her fiancée to come instead. They accepted, and when John Wilkes Booth struck during the third act of Our American Cousin, Major Rathbone attempted to subdue him. Rathbone later explained, “I instantly sprang toward him, and seized him. He wrested himself from my grasp.” Booth produced a long knife and slashed Rathbone’s left arm nearly to the bone, barely missing two major blood vessels. Clara Harris cried out, “Stop that man! The President is shot!” as Booth jumped onto the stage to make his escape.

Rathbone’s physical injuries healed, and he and Clara Harris married in 1867. They eventually had three children, the eldest born on Lincoln’s birthday – February 12 – in 1870. Though Rathbone stayed in the Army for a time and seemed to have an ideal life, many, including his wife, agreed that he was never quite the same after the traumatic events of Lincoln’s murder. He regularly suffered from a host of strange medical problems, which one doctor described as “attacks of neuralgia of the head and face and in the region of the heart attended by palpitations and at times difficulty breathing.” He retired from the Army in 1870, and with the wealth that came to him from both his mother and his stepfather was under no financial pressure to find a new career. In 1877, he unsuccessfully sought a diplomatic appointment in Denmark from the new Rutherford B. Hayes administration. According to friends and later newspaper reports, Rathbone’s life became increasingly tumultuous, and he became obsessed with the idea that his wife and children were about to leave him. Perhaps in an attempt to calm him down and thinking that a change of scenery would help, the Rathbones – Henry, Clara, and their three children, along with Clara’s sister Louise – left the United States and took up temporary residence in Hanover, Germany in 1883.

Things only got worse. Rathbone’s behavior became more bizarre and erratic. He lost weight and claimed to have hallucinations. He refused to allow his wife to sit by the window or be alone as his fears about her desire to leave him increased. On December 24, 1883, Rathbone forced his way into Clara’s room, shot her several times, and then stabbed her in the chest, killing her. He turned the knife on himself, causing injuries so severe that many reported him mortally wounded.

Clara Harris Rathbone was buried in a German cemetery four days after her death. Henry Rathbone, clearly insane, was never tried and was instead confined to a German mental institution for the remainder of his life. He lived another twenty-eight years, dying at age 73 on August 14, 1911. He was interred next to his wife. Decades later, in accordance with a German policy on graves considered “abandoned,” the Rathbones were disinterred and cremated.

What exactly happened to Henry Rathbone’s mental state after the events of April 14, 1865? According to many who knew him, he was obsessed until his dying day with his inability to stop John Wilkes Booth and save Abraham Lincoln’s life. Was his mental decline precipitated by something akin to post-traumatic stress disorder from the twin horrors of Civil War combat and watching Booth murder Lincoln? Some historians and psychiatrists have speculated that Rathbone suffered from schizophrenia or a related malady. His lawyer and friend, G. W. Pope, said: “He was never thoroughly himself after that night…I have no hesitation in affirming that the dreaded tragedy, which preyed upon his nervous and impressionable temperament for many years, laid the seeds of that homicidal mania.”

Regardless of what exactly plagued Rathbone’s mind, it is clear that being unable to prevent Lincoln’s death was a tipping point for him. While few ever consider what happened to the others sitting in the presidential box at Ford’s Theater that night, Henry Rathbone and Clara Harris Rathbone (and Mary Lincoln, for that matter) should be thought of as additional victims of John Wilkes Booth. Both suffered immeasurably for having been there that night. Booth may not have pointed his pistol at them and pulled the trigger, but his actions doomed the Rathbones to lives forever scarred by violence, mental illness, and murder.

Correction: It was brought to our attention that the photograph of Clara Harris we originally included, drawn from the NARA collections, has recently been called into question. We have replaced it with what is now believed to be a correct image.