Benedict Arnold was once a patriotic war hero valued by George Washington and admired by his men. But now his name is synonymous with traitor. What could have led Arnold to ruin his legacy by betraying his fellow Americans during the Revolutionary War?

Analysis of Arnold’s actions have been simplified over the years to serve a narrative of right and wrong. While Arnold’s betrayal was clear—he offered the British seizure of the military fortress at West Point, NY, in exchange for 10,000 pounds and a British military commission—what led up to that moment of betrayal is more complicated and less political than is often taught.

Some would say the catalyst was Pennsylvania Supreme Executive Council President Joseph Reed.

He took a personal dislike to Arnold and, in 1779, attempted to prosecute him on a series of treason charges ranging from buying illegal goods to preferring the company of British loyalists. In the build-up of his case, Reed was known to spread rumors about Arnold without offering proof of his allegations.

Arnold was also deeply in debt and newly married to an ambitious woman. His wife, Peggy, was the daughter of a prominent Philadelphia family with loyalist leanings that had fared better under the British.

Peggy was accustomed to a certain level of living and some historians believe that Peggy steered Arnold to the British in order to maintain that lifestyle. Becoming a traitor to his country could fetch him a handsome payment from the British.

But there were plenty of other reasons, too. Eric D. Lehman, author of Homegrown Terror: Benedict Arnold and the Burning of New London, notes that others at the time had similar circumstances and did not betray their country. Lehman spent time looking over Arnold’s letters and other first-hand accounts.

“Some seemed to point to him ‘lacking feeling,’ i.e. sociopathic, but others showed him having too much feeling—he couldn’t control his temper. The number one thing I found across all of them was his selfish ambition, which came from a profound lack of self-esteem as a child and young man,” Lehman says.

Traditionally Arnold’s story has been taught with a good-versus-evil simplicity. More recently, Lehman points out, the tendency has been to portray Arnold as a misunderstood heroic figure.

“Both simplifications are a mistake in my view,” says Lehman. “He was certainly misunderstood, and he was a hero in the early years of the war. That should always be part of the story.

“But he also betrayed his close friends, was willing to allow the death of and actually kill former comrades, and earned the name ‘traitor’ from both friend and foe. If we leave that out, we simplify the story by omission. If we can’t hold those two ideas in our head at the same time, we are in good company. People like [Marquis de] Lafayette and [George] Washington couldn’t either.”

Lehman thinks it’s important to remember the whole story of Arnold—his betrayal wasn’t just treason. The British, who had much to gain from Arnold switching sides, found him dishonorable and untrustworthy.

“One thing that has been left out of so many tellings of Arnold’s story is that he didn’t stop after his West Point treason was discovered,” Lehman points out. “He went on to attack Virginia—almost capturing Thomas Jefferson—and then attacking Connecticut, his home state.

“Spying was one thing, but his willingness to switch sides in the middle of an armed conflict, and fight against the men who had a year earlier been fighting by his side, was something that people of that time and maybe ours could simply not understand.”