Michel Eyquem, Sieur de Montaigne ( mon-TAYN; French: [miʃɛl ekɛm də mɔ̃tɛɲ]; 28 February 1533 – 13 September 1592), also known as the Lord of Montaigne, was one of the most significant philosophers of the French Renaissance. He is known for popularizing the essay as a literary genre. His work is noted for its merging of casual anecdotes and autobiography with intellectual insight. Montaigne had a direct influence on numerous Western writers; his massive volume Essais contains some of the most influential essays ever written.

During his lifetime, Montaigne was admired more as a statesman than as an author. The tendency in his essays to digress into anecdotes and personal ruminations was seen as detrimental to proper style rather than as an innovation, and his declaration that "I am myself the matter of my book" was viewed by his contemporaries as self-indulgent. In time, however, Montaigne came to be recognized as embodying, perhaps better than any other author of his time, the spirit of freely entertaining doubt that began to emerge at that time. He is most famously known for his skeptical remark, ''Que sçay-je?" ("What do I know?", in Middle French; now rendered as "Que sais-je?" in modern French).