As an English name it has been in use since the Middle Ages, originally in the form Clare, though the Latinate spelling Clara overtook it in the 19th century and became very popular. It declined through most of the 20th century (being eclipsed by the French form Claire in English-speaking countries), though it has since recovered somewhat.
This name was borne by a 12th-century empress of the Latin Empire in Constantinople, who was originally from Flanders. It was also used by her descendants in the royal families of Hungary (spelled Jolánta) and Spain (sometimes spelled Violante). The Blessed Yolanda of Poland was a daughter of Béla IV of Hungary who married a Polish duke. It was also borne by Yolanda of Vianden, a 13th-century countess from Luxembourg who joined a convent against her parents' wishes, later becoming the subject of medieval legend. Another notable bearer was a 15th-century duchess of Lorraine, the subject of the opera Iolanta (1892) by Pyotr Ilyich Tchaikovsky.