Brian Hartley was one of those scholars whose work illuminates his whole field of research - in his case, the contribution that the disciplined study of one class of pottery could make to the understanding of the archaeology of the north-west Roman provinces, by refining the chronology of excavated sites and by revealing unsuspected details of trade and of the organisation and technology of the pottery industry.

Hartley first became involved in archaeology as a schoolboy at King's School, Chester, excavating in Chester itself with Graham Webster and Sir Ian Richmond, and at the nearby site at Heronbridge with W.J. Williams. After National Service in the Royal Air Force and a first degree in Natural Sciences at Trinity Hall, Cambridge, he took the Diploma in Prehistoric Archaeology with distinction, and became Research Assistant at Cambridge under Grahame Clark. His responsibilities were to lecture and supervise in Romano-British archaeology, a discipline that he found much more congenial than prehistory. In 1956 he was appointed to a lectureship in the Department of Latin at Leeds University, where he stayed until his retirement in 1995.

This seemingly quiet career conceals a major contribution to the archaeology of the north-western provinces of the Roman Empire. His excavations on military sites in Yorkshire during the 1960s did much to elucidate the history of the area during the Roman period. But it is his work on pottery, notably the fine red pottery known as Samian ware which was imported to Britain in large quantities from France and Germany, that has had the greatest impact for the chronology and interpretation of archaeological sites.

He early recognised that pottery could become an essential tool in establishing the chronology of sites, as well as providing specific information on both local and long-distance trade and on the technology and skills used to manufacture different wares. His friendship with two of the pioneers of Romano-British pottery studies, Philip Corder and John Gillam, and his own excavations at kiln-sites in the Nene Valley, Northamptonshire, showed that the study of Samian, with its more rapidly changing forms and its potential for relatively precise dating, could be used to provide a firmer chronology for other wares that were made and traded more locally.

In 1963, he began the work that would occupy much of his spare time for the rest of his life, a study of the potters who worked in the Samian industry. Most Samian ware carries the name stamp of the potter who made it and, in collecting records of hundreds of potters, distinguishing those with the same name, identifying the individual dies that they used, and establishing the dates when they were working, Hartley's study has added incalculably to the value of Samian as a dating tool.

It has also revealed much fine detail on the mechanism, and occasional quirks, of the pottery trade, and on the organisation of the workshops themselves, where graffito records show that kilns firing up to 30,000 pots at a time were the norm. A landmark paper on the Roman occupation of Scotland, published in the journal Britannia in 1972, showed how the advance in Samian studies could be used to illuminate not merely the dating of individual sites but wider aspects of the history of the province.

The material gathered for this index of stamps came from excavations and museum collections all over the north-western Roman provinces: workshops such as the French potteries at La Graufesenque, and at Lezoux where Hartley excavated with Sheppard Frere in the 1960s, and other sites ranging from provincial capitals and military headquarters down to the humblest of rural farmsteads.

Hartley was fortunate in his assistants, Felicity Wild and later Brenda Dickinson, but his own generosity in dating finds for excavators and in sharing his information was crucial in ensuring that so much data has been accumulated. One recent result has been the 13-volume corpus of stamped and decorated bowls manufactured at La Graufesenque, published last year by the Römisch-Germanisches Museum at Mainz. While the final text of the index itself was unfinished at Hartley's death, it is the intent of his friends and colleagues to bring it to completion.

Apart from his archaeological studies, Brian Hartley was an enthusiastic cook with an appreciation of good food and wine, loved Baroque music, especially J.S. Bach, pursued his family's genealogy and took great pleasure in the restoration of his 18th-century house in York. He was wonderful company and a kind and supportive friend and colleague, with a dry wit and the true raconteur's gift with a story - no one who heard his deceptively simple account of missing a succession of trains in the company of John Gillam will ever forget it.