The Benedictine Confederation is a union of monastic congregations that nevertheless retain their own autonomy, established by Pope Leo XIII in his brief "Summum semper" (12 July 1893), subsequently approved by his successors. Pope Pius XII explicitly ordered this union to be regulated by a "Lex Propria", which was later revised after the Second Vatican Council.
Read more about Benedictine Confederation: Organization of The Benedictine Confederation, Congregations of Benedictine Monks, List of The Abbots Primates of The Benedictine Confederation