William R. Day, Jr, was responsible, in collaboration with Philip Grierson, Alan M. Stahl, and Lucia Travaini, for Medieval European Coinage 13: Italy (II) (Central Italy), i. e. Emilia-Romagna, Tuscany, Umbria, the Marches, and Rome and Lazio. He also collaborated with Philip Grierson, Michael Matzke, and Andrea Saccocci on Medieval European Coinage 12: Italy (I) (North Italy), i. e. the Piedmont, Liguria, Lombardy, the greater Veneto (incl. Trentino-Alto Adige/Südtirol, Friuli-Venezia Giulia). He is a contributing author for both volumes and remains responsible for co-ordinating the contributions of other authors and preparing the appendices, catalogue and photographic plates.
2008-9 Jean-François Malle Fellow, Villa I Tatti (Harvard University Center for Italian Renaissance Studies, Florence)
2001-8 Research Associate, Department of Coins and Medals, Fitzwilliam Museum
2000-1 Part-time Lecturer, Department of Medieval and Modern History, University of Birmingham: 'Florence, 1000-1500: the foundations of the renaissance'
1999-2000 Teaching Assistant, Department of Medieval and Modern History, University of Birmingham
1994-9 Ph. D., London School of Economics and Political Science. Dissertation, The early development of the Florentine economy, c. 1100-1275
1995-6 Visiting Researcher, European University Institute (Florence, Italy), Department of History and Civilisation
1991-4 M. A., Catholic University of America (Washington, DC, USA), Medieval History. Master's thesis, 'The circulation of money in early medieval southern Italy, c. 750-1075'.
1979-82 & 1988-91 B. A., Towson State University (Towson, Maryland, USA), History. Senior thesis, 'Crisis and innovation: guelfs, ghibellines, and historiography in late medieval Florence'.
6-7 September 2007 Organising conference The Debasement of Coinage in Medieval Europe and the Mediterranean, c. 1000-1500, at Gonville & Caius College, Cambridge.
10-12 July 2007 Co-organising strand (with Edward Coleman, University College Dublin), Cities in Medieval Italy and Italians in Medieval Cities, 8 sessions, International Medieval Congress, University of Leeds.
7-8 September 2005 Organised conference Roma Caput Mundi: the administrative, economic & political background to the coinage and monetary history of Rome & the Papal States, c. 1000-1500, at Gonville & Caius College, Cambridge.
3-4 April 2003 Organised conference Medieval Italy I: Transition and transformation in Medieval Italy, c. 500-1000, at Gonville and Caius College, Cambridge.
Italy, c. 750-1500, economic and monetary history, numismatics.
'A small hoard of Venetian grossi from Jordan' in Cercetari numismatice (Muzeul national de istorie a României) 12 (2006), in press
'Florentine mint-masters abroad and the commercial revolution of the Middle Ages' in Travel and Movement in Medieval and Renaissance Italy (Aldershot: Ashgate Publishers), in press
'The imitation gold florin of the «ex» marquises of Carretto, Piedmont, c. 1350' in Rivista italiana di numismatica e scienze affini 107 (2006), 447-69
'The land market in pre-industrial Europe: some implications of recent research on the rural economy (review essay)', Le Marché de la terre au Moyen Âge, eds Laurent Feller & Chris Wickham (Rome: École française de Rome, 2005; Collection de l'École française de Rome 350), 49-61 & 659-60
'The petty coinage of Genoa under the early doges, 1339-1396', XIII Congreso internacional de numismática (Madrid, 15-19 septiembre 2003): Actas – Proceedings – Actes, eds C. Alfaro, C. Marcos & P. Otero, 2 vols (Madrid: Ministerio de cultura, 2005), 1295-1304.
'Early imitations of the gold florin of Florence and the imitation florin of Chivasso in the name of Theodore I Paleologus, Marquis of Montferrat (1306-1338)', Numismatic Chronicle 164 (2004), 183-199
'L'agontano di Chiusi' (co-authored with Lucia Travaini), L'agontano: una moneta d'argento per l'Italia medievale, Convegno in ricordo di Angelo Finetti, Trevi (Perugia), 11-12 ottobre 2001, ed. Lucia Travaini (Perugia: Centro Stampa della Regione di Umbria, 2003), 141-152
'The population of Florence before the Black Death: survey and synthesis', Journal of Medieval History 28 (2002), 93-129.
'Population growth and productivity: rural-urban migration and the expansion of the manufacturing sector in thirteenth century Florence', in Labour and labour markets between town and countryside (middle ages - 19th century), eds Bruno Blondé, Eric Vanhaute, Michèle Galand (Turnhout, Belgium: Brepols Publishers, 2001), 82-110.
'The monetary reforms of Charlemagne and the circulation of money in early medieval Campania', Early Medieval Europe 6 (1997), 25-45.
Forthcoming: Florence before Dante: the early development of the Florentine economy, c. 1115-1265 (under contract with Brill Publishers, Leiden, Netherlands)