Wenham graduated from Durham University in 1933 with an honours degree in modern history. He spent some time excavating under Eric Birley in the civilian settlement at Housesteads Roman Fort on Hadrian's Wall. During the Second World War he served with the Royal Army Ordnance Corps. In 1951, he was appointed lecturer in history at St. John's College, York. He would later become head of the History department and remained part of the College until his retirement in 1974. Wenham was a prolific excavator in and around York, frequently publishing his excavations with the Yorkshire Archaeological Society. He had a particular interest in the defences of the Fortress at Eboracum. He excavated throughout the city during the 1950s, 60s and 70s, at locations including King's Square, Davygate, Petergate and St Mary Bishophill Junior, York. His excavations at Trentholme Drive resulted in the first comprehensive report of a Romano-British Cemetery; it had been excavated as part of an archaeological investigation rather than during building work. Wenham was the editor of the Yorkshire Archaeological Journal between 1955-1968. He was elected a Fellow of the Society of Antiquaries of London on 8 January 1970. After retirement, Wenham moved to his native Richmond.
Publications
Wenham, L. P. 1954. 'Blossom Street Excavations 1953'. Yorkshire Arhchitectural and York Archaeological Society Proceedings Vol. 11. pp: 523-4
Wenham, L. P. 1958. The History of Richmond School, Yorkshire. Herald Press
Wenham, L. P. 1960. 'Seven archaeological discoveries in Yorkshire'. Yorkshire Archaeological Journal Vol. 40. pp: 298-328
Wenham, L. P. 1961. 'Excavations and discoveries adjoining the south-west wall of the Roman legionary fortress in Feasegate, York, 1955-7'. Yorkshire Archaeological Journal Vol. 40. pp:329-50
Wenham, L. P. 1962 'Excavations and discoveries within the Legionary Fortress in Davygate, York, 1955-8'.Yorkshire Archaeological Journal Vol. 40. pp:507-87
Wenham, L. P. 1965 'The South-West defences of the Fortress of Eboracum' in Jarrett, M. G. and Dobson, B. Britain and Rome. pp: 1-26
Wenham, L. P. 1967 'Two Excavations: No.2 Ryethorpe Grange and Appletree Farm, York, 1959'. Transactions of the Yorkshire Philosophical Society pp: 45-60
Wenham, L. P. 1968 'Discoveries in King's Square, York, 1963'. Yorkshire Archaeological Journal Vol. 42. pp: 165-8
Wenham, L.P., Warwick, R., Cooke, C., Rowbotham, T. C. 1968. The Romano-British Cemetery at Trentholme Drive, York. Ministry of Public Buildings and Works Archaeological Report no. 5. London: HSMO
Wenham, L. P. 1972. 'Excavations in Low Petergate, York, 1957-8'. Yorkshire Archaeological Journal Vol. 44. pp: 65-113