Objective: To evaluate and differentially diagnose erosive skeletal lesions located on multiple joints of an individual archaeologically recovered in 2017. Materials: Skeletal remains of a well-preserved skeleton dating to the 12th-13th centuries from the Medieval church of San Biagio in Cittiglio (Varese, northern Italy). Methods: Macroscopic and radiographic imaging. Results: Erosive marginal symmetrical lesions are present on the metatarsophalangeal, metacarpophalangeal and interphalangeal joints of an adult male, aged 55-75 years. Osteolytic changes, in the form of pocket erosions, surface resorptions, and pseudocyst formations, are also macroscopically observed on some carpal and tarsal bones and on several large peripheral joints. Conclusions: A careful differential diagnosis of the lesions and their macroscopic and radiological appearance are suggestive of a case of rheumatoid arthritis-like polyarthropathy. Significance: This case contributes to the debate regarding the antiquity of erosive polyarthropathies, providing additional evidence for the existence of these diseases in the Old World prior to the discovery of the Americas. Limitations: Small sample size limits the discussion of the scope of the disease in antiquity. Suggestions for Further Research: This case highlights the need for further macroscopic, radiographic, and biomolecular studies of premodern European skeletal samples to investigate the hypothesized pre-existence of these pathological conditions in Europe prior to 1492.