He was the son of Nathaniel Clayton, Town Clerk of Newcastle upon Tyne from 1785 to 1822, and his wife Dorothy Atkinson, daughter of George and
Bridget Atkinson of
Temple Sowerby. He went to
Kirkoswald School in
Westmorland, and received a classical education at
Uppingham School in
Rutland. He began work in the firm of solicitors that had been established by his father Nathaniel in the
Bigg Market in Newcastle in 1778, and which became Clayton & Dunn, and qualified as an attorney in 1815. John became Under-Sheriff in 1816 before succeeding his father as Town Clerk in 1822, remaining in post until 1867. He never married, but shared the family's townhouse in Fenkle Street, Newcastle, with his unmarried brother and legal partner, Matthew. As well as his work in the city, Clayton was an
antiquarian. Four years after his birth in 1792, his father purchased the
Chesters Estate, through which
Hadrian's Wall runs, and which contained the site of Chesters fort. Landscaping a parkland setting for his home, The Chesters, Nathaniel Clayton levelled out and grassed over much of the Roman fort. While doing so he collected antiquities. From an early age John Clayton took a serious interest not only in the fort of Chesters and its immediate surroundings, but also in Roman remains in the nearby countryside. From 1834 Clayton began buying land to preserve the Wall, now a
World Heritage Site, which was subject to the removal of stones for reuse. He had some restoration work carried out on parts of the Wall. He helped preserve that central stretch of Hadrian's Wall that includes
Chesters (Cilurnum).
Housesteads and
Vindolanda, and carried out some of the first archaeological excavations on the Wall. His first published work, in 1843, was his excavation of the commanding officer's bath-house at Chesters. He was involved in excavations most years for the next half-century, both at Chesters and elsewhere along Hadrian's Wall, namely Cawfields (
Milecastle 42), Castle Nick (
Milecastle 39) and Housesteads Crags (
Milecastle 37), Housesteads and
Carvoran. His archaeological work continued into his later years, and he was in his early nineties when he uncovered the spectacular sculptures of the temple to Mars Thincsus at Housesteads. Clayton established Chesters as an archaeological site open to visitors. A small garden pavilion on the estate was used to display his archaeological collection, as well as other casual finds and purchased acquisitions, at Chesters. Following his death in 1890, his nephew Nathaniel commissioned and had built a permanent museum, completed in 1896, to house the Clayton Collection. Ownership of the collection was transferred to the newly formed Trustees of the Clayton Collection in 1930 under a
deed of trust and it is now curated by
English Heritage. ==Grainger's plan for Newcastle==