Beate Barbara Juliane Freifrau von Krüdener, often called by her formal French name, Madame de Krüdener, was a Baltic German religious mystic, author, and Pietist Lutheran theologian who exerted influence on wider European Protestantism, including the Swiss Reformed Church and the Moravian Church, and whose ideas influenced Tsar Alexander I of Russia.

Pietism, also known as Pietistic Lutheranism, is a movement within Lutheranism that combines its emphasis on biblical doctrine with an emphasis on individual piety and living a holy Christian life.