A historian has called for official recognition after identifying a steel helmet in the Metropolitan Museum of Art’s collection as belonging to Osman Ghazi, the eponymous founder of the Ottoman Empire.

A historian has called for official recognition after identifying a steel helmet in the Metropolitan Museum of Art’s collection as belonging to Osman Ghazi, the eponymous founder…

A researcher specializing in the early history of the Ottoman Empire says he has identified what he believes is a steel helmet belonging to Osman I, the...