Marie Anne Adelaide Lenormand was born on 27 May 1772 in Alencon, Normandy, and was orphaned by the age of five, educated afterward in a Benedictine convent school. At fourteen she ran away from the school and made her way to Paris alone, where she learned cartomancy, the reading of playing cards for divination, and began building a clientele. Her earliest recorded readings, given during the turmoil of the French Revolution, reportedly included figures such as Jean-Paul Marat, Maximilien Robespierre and Louis Antoine de Saint-Just, though the more dramatic anecdotes attached to these consultations are difficult to verify independently and are treated by historians with some caution.
Her defining relationship was with Josephine de Beauharnais, who consulted her before her marriage to Napoleon Bonaparte and reportedly continued to do so as empress; Lenormand's later published accounts claimed she had predicted key turns in both Josephine's and Napoleon's fortunes, including his eventual exile, claims that cannot be independently verified and that Lenormand herself, as their sole source, had every incentive to embellish after the fact. She worked as a professional cartomancer for roughly forty years and died in Paris on 25 June 1843.