The New Middle Ages is a 20-book series with 20 released primary works first released in 1133 with contributions by Pierre Abélard, Héloïse d'Argenteuil, Heloise, Frances A. Underhill, Sarah L. Higley, Albrecht Classen, Susan Signe Morrison, Roger A. Ladd, and Jóhanna Katrín Friðriksdóttir.