Когда была сделана первая железная клетка?
The original German term is "stahlhartes Gehäuse" (steel-hard casing); this was translated into "iron cage", an expression made familiar to English language speakers by Talcott Parsons in his 1930 translation of Weber's "The Protestant Ethic and the Spirit of Capitalism". This choice has been questioned recently by scholars who prefer the more direct translation: "shell as hard as steel".
1930