He is perhaps best known for his honesty — but a lesser-known fact about Abraham Lincoln is that the 16th president of the United States battled severe depression during his lifetime.

Dr. Chris Tuell, a clinical psychotherapist and a chemical and behavioral addiction specialist at the University of Cincinnati College of Medicine, has studied Lincoln’s mental health struggles extensively.

“Though the history books play a significant role in our perception and understanding of the ‘rail splitter’ from Illinois, it often becomes easy for us to forget that Abraham Lincoln was very human,” Tuell told Fox News Digital.

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“Lincoln led this nation through its worst crisis, while at the same time battling his own internal war of chronic depression.”

Here’s what to know. 

Signs of Lincoln’s depression

At age 32, in a letter to John Stuart in 1841, Lincoln wrote, “I am now the most miserable man living. If what I feel were equally distributed to the whole human family, there would not be one cheerful face on earth. Whether I shall ever be better, I cannot tell; I awfully forebode I shall not; to remain as I am is impossible.” 

Lincoln scholars have “clear evidence” that he suffered from depressive episodes beginning in his 20s, Tuell noted.

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“Lincoln’s school teacher, Mentor Graham, stated, ‘Lincoln told me that he felt like committing suicide often,’” Tuell said.  

“Law partner and biographer William Herndon stated, ‘He was a sad-looking man, gloomy and melancholic. His melancholy dripped from him as he walked.’”

Contributing factors to Lincoln’s depression

The president’s mental health condition can be attributed to both genetics and traumatic experiences, according to the book “Lincoln’s Melancholy” by Joshua Wolf Shenk.

Lincoln is said to have had a family history of depression.

“Historical records indicate that Lincoln’s mother and father were disposed to melancholy and that one side of the family ‘was thick with mental disease,’” said Tuell. 

“Bereavement in childhood can be one of the most significant factors in the development of depressive illness in later life.”

As a child, Lincoln lost several close family members. 

After his brother died in infancy, Lincoln’s mother, aunt and uncle all died when he was just 9 years old. A decade later, his sister died while delivering a stillborn infant.

Later, Lincoln experienced the loss of his first love, Ann Rutledge, in 1835. 

As a father, he experienced the death of two young sons, Eddie and Willie. 

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“According to mental health professionals, bereavement in childhood can be one of the most significant factors in the development of depressive illness in later life,” Tuell said. 

Dr. Marc Siegel, clinical professor of medicine at NYU Langone Medical Center and a Fox News medical contributor, said that Lincoln’s melancholy may have been tied to his “intellectual prowess and [his tendency to] see and feel things deeply.”

How Lincoln dealt with depression

Before the age of psychotherapy and antidepressant medications, Lincoln learned to live with his depressive disposition, Tuell said. 

“He would frequently use humor and storytelling to elevate his mood and distract himself from his depression,” the psychologist told Fox News Digital.  

“Only his closest friends had any insight concerning the extent of his condition.”

In a time period when mental health treatment was not available, Tuell noted that learning how to manage his life with his depression was Lincoln’s only choice.  

“The only other option would have been for him to succumb to these adversities,” he said. 

“He managed to overcome it and the Civil War to become our greatest president, by most people’s estimation.”

“It does not appear that it was in the 16th president’s persona to acquiesce. Lincoln persevered and served this country eloquently.”

Siegel noted that in Lincoln’s time, depression was referred to as “melancholy” and was typically treated with opium, a highly addictive narcotic drug that is extracted from the poppy plant.

Historians have noted that Lincoln’s sons brought him periods of happiness despite his ongoing depression.

“We are so used to seeing Abraham Lincoln looking depressed and sad, that we forget — and the historical record is clear on this — he would break down in laughter when playing with his boys or observing the mayhem they created,” Raymond Arroyo, a Fox News contributor and bestselling author, previously told Fox News Digital. 

He is the author of the book, “The Magnificent Mischief of Tad Lincoln,” part of his Turnabout Tales series of books. 

What to know about depression

Depressive disorders affect approximately 18.8 million American adults or about 9.5% of the U.S. population age 18 and older in a given year, according to the National Institute of Mental Health. 

There are different types of depressive disorders, according to Tuell.

These may include major depression, dysthymia (an ongoing, low-grade depression) and bipolar (mood swings of depression and mania).

“Depression can affect every aspect of one’s life — physical health, sleep [habits], eating habits, job and your relationships with friends and family,” said Tuell. “It affects thoughts, feelings and behaviors.”

While depression is one of the most serious mental health issues facing people today, Tuell noted that it’s also one of the most treatable.

Lincoln’s perseverance in the face of severe depression was something to be admired, Tuell and Siegel agreed.

“We can only speculate what Lincoln would say or do about our current state of political affairs, or even what thoughts he may have toward the new millennium’s understanding of depression and mental health,” Tuell said.  

“But now, some 159 years later, Lincoln’s historical persona continues to belong to the ages.”  

Lincoln believed in the human spirit and spoke of the role people must have toward one another, Tuell noted. 

“This was no more clearly expressed than through Lincoln’s own words, ‘With malice toward none; with charity for all,’” he said.

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Lincoln’s battle with depression can be regarded as an “inspiration to all who suffer from this dreaded disease or feel stigmatized by it,” Siegel added.

“He managed to overcome it and the Civil War to become our greatest president, by most people’s estimation.”

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