Declare (2001) is a supernatural spy novel by Tim Powers. It presents a secret history of the cold war in which an agent for a secret British spy organization learns the true nature of several beings living on Mount Ararat. In this he is opposed by real-life communist traitor Kim Philby, who did travel extensively in the region. Philby's father, St. John Philby, was a noted Arabist whose book The Empty Quarter (on the Rub' al Khali) was extensively used as source material for the novel.
In 2001 Declare won both the World Fantasy Award for Best Novel and the International Horror Guild Award for Best Novel. It also appeared on the final ballot for the Nebula Award, however it was later determined to be ineligible due to the limited edition that appeared the year prior to the trade edition.