In 2015, in order to commemorate the ninth centennial of the death of the Great Countess Matilda of Canossa, four sessions and a roundtable discussion were organized under the rubric Matilda 900. These sessions took place at the 50th International Congress on Medieval Studies (University of Western Michigan, Kalamazoo, MI) in the US and the Leeds International Medieval Congress (University of Leeds) in the UK. Papers were read by scholars from Australia, Canada, Ireland, Italy, the UK and the USA. The Kalamazoo Congress is the world’s largest gathering of scholars of the Middle Ages, and, although a number of papers were read over the years, there had been no session devoted to Matilda in the previous thirty years, if ever. The Leeds Congress attracts more participants from European countries, but the sessions held at the 2015 conference were the first devoted to Matilda, as nearly as could be determined. Thus, a major goal of Matilda 900 was to ensure that the Great Countess’ ninth centennial did not pass without notice alongside the commemorations of Azincourt (1415), Magna Carta (1215) and the Fourth Lateran Council (1215), events that are much better known in English-language scholarship. It is especially gratifying that scholars from Italy joined the sessions.