Edgar Allan Poe's The Murders in the Rue Morgue introduced the analytical character Dupin. Observation and analysis explain the case, making it an important early work of detective fiction.

Dupin is not a typical detective within a modern police organization. The story influenced later mystery structures and shows how a process of thought can become a narrative.

Military career

As Poe was unable to support himself, he decided to enlist in the United States Army as a private on May 27, 1827, using the name "Edgar A. Perry". Although he claimed that he was 22 years old, he was actually 18. He first served at Fort Independence in Boston Harbor for five dollars a month. That same year, his first book was published, a 40-page collection of poetry titled Tamerlane and Other Poems, attributed only to "A Bostonian". 50 copies were printed, and the book received virtually no attention.

Poe's 1st Regiment of Artillery was posted to Fort Moultrie in Charleston, South Carolina, before embarking on the brig Waltham on November 8, 1827. Poe was promoted to "artificer", an enlisted tradesman tasked with preparing shells for artillery. His monthly pay doubled. Poe served for two years, attaining the rank of sergeant major for artillery, the highest rank that a non-commissioned officer could achieve. He then sought to end his five-year enlistment early.

Poe revealed his real name and his actual circumstances to his commanding officer, Lieutenant Howard, who promised to allow Poe to be honorably discharged if he reconciled with Allan. Poe then wrote a letter to Allan, who was unsympathetic and spent several months ignoring Poe's pleas. Allan may not have written to Poe to inform him of his foster mother's illness. Frances Allan died on February 28, 1829. Poe visited the day after her burial. Perhaps softened by his wife's death, Allan agreed to support Poe's desire to receive an appointment to the United States Military Academy at West Point, New York.

Poe was finally discharged on April 15, 1829, after securing a replacement to finish his enlistment. Before entering West Point, he moved to Baltimore, where he stayed with his widowed aunt, Maria Clemm, her daughter Virginia Eliza Clemm (Poe's first cousin), his brother Henry, and his invalid grandmother Elizabeth Cairnes Poe. That September, Poe received "the very first words of encouragement I ever remember to have heard" in a review of his poetry by influential critic John Neal, which prompted Poe to dedicate one of the poems to Neal in his second book, Al Aaraaf, Tamerlane and Minor Poems, published in Baltimore in 1829.

Poe traveled to West Point and matriculated as a cadet on July 1, 1830. In October 1830, Allan married his second wife Louisa Patterson. This marriage, and the bitter quarrels with Poe over children born to Allan out of extramarital affairs, led to the foster father finally disowning Poe. Poe then decided to leave West Point by intentionally getting court-martialed. On February 8, 1831, he was tried for gross neglect of duty and disobedience of orders for refusing to attend formations, classes, and church. Knowing he would be found guilty, Poe pleaded not guilty to the charges in order to induce dismissal. During his time at West Point, he is known to have frequented a tavern run by Benny Havens, whom Poe allegedly referred to as "the only congenial soul in this God-forsaken place".

Literary theory

Poe's writings often reflect the literary theories he introduced in his prolific critical works and expounded on in such essays as, "The Poetic Principle". He disliked didacticism and imitation masquerading as influence, believing originality to be the highest mark of genius. In Poe's conception of the artist's life, the attainment of the concretization of beauty should be the ultimate goal. That which is unique is alone of value. Works with obvious meanings, he wrote, cease to be art. He believed that any work worthy of being praised should have as its focus a single specific effect. That which does not tend towards the effect is extraneous. In his view, every serious writer must carefully calculate each sentiment and idea in their work to ensure that it strengthens the theme of the piece.