Frank Belknap Long (1901–1994) was an American writer, born in Manhattan and died in New York City. His 1921 story "The Eye Above the Mantel" caught H. P. Lovecraft's attention, sparking a friendship that lasted until Lovecraft's death in 1937; the two exchanged more than a thousand letters.
Long wrote the first Mythos story by anyone other than Lovecraft, "The Hounds of Tindalos," introducing incomprehensibly alien beasts emerging from strange angles in dim recesses of non-Euclidean space. He also created Chaugnar Faugn.
After selling his first story, "The Desert Lich," to Weird Tales in 1924, he became a frequent contributor for decades, leaving behind 29 novels and some 150 short stories as one of the founding voices of cosmic horror.