Legatus: The Papal Legate in the Kingdom of Hungary, Transylvania and the Holy See, 1100–1400

Legatus — the papal legate — is the pope's personal representative acting with delegated authority. Classical canon law recognised three grades: the legatus a latere (cardinal legate, fullest powers), the legatus missus (non-cardinal, specific commission), and the legatus natus (archbishop whose see permanently carried a legatine dignity — in Hungary, the Archbishop of Esztergom). The legal framework is in Gregory IX's Decretals X 1.30 (De officio legati) and in Hostiensis, Summa Aurea I De officio legati and Lectura on X 1.30. This study traces legatus and its forms in 823 charter records for Hungary and Transylvania and 2,785 for the papal curia, 1100–1400, from the archive of the Florilegium Reipublicae Christianae (corpus snapshot of 13 November 2026). The curial record peaks sharply in 1175–1274 (1,308 records), reflecting the Innocentian registers and the Decretalist era, then drops after the Avignon transfer (160 in 1275–1299, rising again under John XXII and Benedict XII). The Hungarian corpus is dominated before 1300 by legatine activity connected to the Third Crusade, the Golden Bull crisis of 1231–32, and the Mongol aftermath, with the regal issuer group (260 records) consistently largest. After 1300 the Angevin restoration brings Gentilis de Monteflorum (1308–11), whose legation produced 247 records in the 1300–1324 quarter — the single largest Hungarian burst in the entire period. The legatus natus dignity of the Archbishop of Esztergom appears in 5 records; the nuntius apostolicus in 2, reflecting the form's emergence in the later 14th century. This study is a corpus study: it counts and reads what a large body of edited medieval documents says about one concept, and sets that against modern scholarship. It was prepared with software and AI assistance. The counts, tables, charts and first draft were generated by a program (publisher.py) from the author's corpus, without a language model. The search rules, the concept's introductory paragraphs and the interpretive paragraphs were written with the help of an AI system (Claude, Anthropic), and a random sample of the matches was read in full to measure how many are true instances (section 2). The author read and approved the text before publication. Readings of the Latin marked as preliminary have not yet had a specialist's close reading. The counts depend on what the editions print and how their editors summarised it: editions are uneven by region and decade, modern summaries carry their editors' interpretations, and OCR may miss or misread words, so the numbers show proportions and trends, not totals. The study has not been peer reviewed. Corrections are welcome and will be published as new versions of this record.