Louis-Édouard-François-Desiré Pie (26 September 1815 – 18 May 1880), also referred to as Cardinal Pie, was a French Catholic bishop of Poitiers and cardinal, known for his ultramontanism and defence of the social reign of Christ the King.
Pie was born in Pontgouin in the diocese of Chartres on 26 September 1815, just after the Napoleonic Wars, between the Battle of Waterloo (18 June 1815) and the Treaty of Paris (20 November 1815). In 1835, Pie entered the seminary of St. Sulpice, where he remained for four years. He then continued his theological studies in Paris. While developing a reputation for arguing the ultramontane cause against Gallican professors, the young priest developed a friendship with Abbé Lecomte, pastor of the Cathedral of Chartres. Abbé Lecomte, who had repeatedly refused episcopal appointment, was an ultramontane defender of papal infallibility, and a great admirer of the thought of Joseph de Maistre. Increasingly taking on the role of protector and spiritual father to Pie, Lecomte's death – which occurred on 31 December 1850 – was a very painful episode for Pie, who had risen at his relatively young age to occupancy of the see of Poitiers. He wrote the same day the brother of his deceased friend, Gabriel Lecomte: "I have no words, sir, and worthy friend, to express my excessive pain (...) I loved as a father, as a brother, as a unique friend, he for whom death came knocking. I can not stop the course of my tears, and yet still they are insufficient to unload my heart." Another man who played a leading role in the life of Abbé Pie was his bishop, who knew him as a seminarian and later as a young priest and vicar of Chartres. Bishop Clausel Montale was the chaplain of Madame la Dauphine, Duchesse d'Angoulême, before being named bishop of Chartres.