Nathaniel Parker Willis (January 20, 1806 – January 20, 1867), also known as N. P. Willis, was an American writer, poet and editor who worked with several notable American writers including Edgar Allan Poe and Henry Wadsworth Longfellow. He became the highest-paid magazine writer of his day. His brother was the composer Richard Storrs Willis and his sister Sara wrote under the name Fanny Fern. Harriet Jacobs wrote her autobiography while being employed as his children's nurse.

Born in Portland in what was then the District of Maine, Willis came from a family of publishers. His grandfather Nathaniel Willis owned newspapers in Massachusetts and Virginia, and his father Nathaniel Willis was the founder of Youth's Companion, the first newspaper specifically for children. Willis developed an interest in literature while attending Yale College and began publishing poetry. After graduation, he worked as an overseas correspondent for the New York Mirror. He eventually moved to New York and began to build his literary reputation. Working with multiple publications, he was earning about $100 per article and between $5,000 and $10,000 per year. In 1846, he started his own publication, the Home Journal, which was eventually renamed Town & Country. Shortly after, Willis moved to a home on the Hudson River where he lived a semi-retired life until his death in 1867.

Willis embedded his own personality into his writing and addressed his readers personally, specifically in his travel writings, so that his reputation was built in part because of his character. Critics, including his sister in her novel Ruth Hall, occasionally described him as being effeminate and Europeanized. Willis also published several poems, tales, and a play. Despite his intense popularity for a time, at his death Willis was nearly forgotten.

Nathaniel Parker Willis was born on January 20, 1806, in Portland, Maine. His father Nathaniel Willis was a newspaper proprietor there and his grandfather owned newspapers in Boston, Massachusetts, and western Virginia. His mother was Hannah Willis (née Parker) from Holliston, Massachusetts, and it was her husband's offer to edit the Eastern Argus in Maine that caused their move to Portland. Willis's younger sister was Sara Willis Parton, who would later become a writer under the pseudonym Fanny Fern. His brother, Richard Storrs Willis, became a musician and music journalist known for writing the melody for "It Came Upon the Midnight Clear". His other siblings were Lucy Douglas (born 1804), Louisa Harris (1807), Julia Dean (1809), Mary Perry (1813), Edward Payson (1816), and Ellen Holmes (1821).

In 1816, the family moved to Boston, where Willis's father established the Boston Recorder and, nine years later, the Youth's Companion, the world's first newspaper for children. The elder Willis's emphasis on religious themes earned him the nickname "Deacon" Willis. After attending a Boston grammar school and Phillips Academy at Andover, Nathaniel Parker Willis entered Yale College in October 1823 where he roomed with Horace Bushnell. Willis credited Bushnell with teaching him the proper technique for sharpening a razor by "drawing it from heel to point both ways ... the two cross frictions correct each other". At Yale, he further developed an interest in literature, often neglecting his other studies. He graduated in 1827 and spent time touring parts of the United States and Canada. In Montreal, he met Chester Harding, with whom he would become a lifelong friend. Years later, Harding referred to Willis during this period as "the 'lion' of the town". Willis began publishing poetry in his father's Boston Periodical, often using one of two literary personalities under the pen names "Roy" (for religious subjects) and "Cassius" (for more secular topics). The same year, Willis published a volume of poetical Sketches.

In the latter part of the 1820s, Willis began contributing more frequently to magazines and periodicals. In 1829, he served as editor for The Token, making him the only person to be editor in the gift book's 15-year history besides its founder, Samuel Griswold Goodrich. He used the position to solicit a short story from fellow Portland native, John Neal, who continued contributing tales and essays well into the 1830s. Also in 1829, Willis founded the American Monthly Magazine, which began publishing in April of that year until it was discontinued in August 1831. He blamed its failure on the "tight purses of Boston culture" and moved to Europe to serve as foreign editor and correspondent of the New York Mirror. In 1832, while in Florence, Italy, he met Horatio Greenough, who sculpted a bust of the writer. Between 1832 and 1836, Willis contributed a series of letters for the Mirror, about half of which were later collected as Pencillings by the Way, printed in London in 1835. The romantic descriptions of scenes and modes of life in Europe sold well despite the then high price tag of $7 a copy. The work became popular and boosted Willis's literary reputation enough that an American edition was soon issued.

Despite this popularity, he was censured by some critics for indiscretion in reporting private conversations. At one point he fought a bloodless duel with Captain Frederick Marryat, then editor of the Metropolitan Magazine, after Willis sent a private letter of Marryat's to George Pope Morris, who had it printed. Still, in 1835 Willis was popular enough to introduce Henry Wadsworth Longfellow to important literary figures in England, including Ada Byron, daughter of Lord Byron.

While abroad, Willis wrote to a friend, "I should like to marry in England". He soon married Mary Stace, daughter of General William Stace of Woolwich, on October 1, 1835, after a month-long engagement. The couple took a two-week honeymoon in Paris. The couple moved to London where, in 1836, Willis met Charles Dickens, who was working for the Morning Chronicle at the time.