Poleyn

Poleyn is the knee defense in classic plate armor, a protective element designed to cover and articulate the knee joint. It forms the central portion of leg armor along with the cuisses (thigh armor) above and the greaves below, and it was essential for protecting one of the most exposed joints in combat.

Construction and design typically involve one or more plates shaped to follow the curve of the knee. A poleyn may be a single curved plate or a series of lames riveted and hinged together to allow bending. The edges are often contoured to protect the patella and to deflect blows, and many examples include side wings or flanges to shield the knee’s lateral areas. The poleyn is usually connected to the thigh piece at the upper end and to the greave or lower leg protection at the lower end, allowing the knee to flex while remaining protected.

Historically, poleyns appear in European armor from the late medieval period and were widespread through the 15th and into the 16th centuries. Variants existed across regions, with differences in shape and articulation reflecting evolving techniques in plate armor and the demands of warfare and tournament life. Over time, improvements in overall plate integration and articulation gradually altered how the knee region was armored, but the poleyn remained a defining feature of the era’s armor design.

In modern contexts, poleyns are studied in museums and by armor enthusiasts as examples of medieval and early modern protective technology. See also armor, plate armor, cuisse, and greave.