There is much misunderstanding about the name of the theme perfected by Lully. The term Folia is used to refer to both the old variations and to the basic form as developed by Lully, leading to much confusion. Some composers have even written variations on both types of Folia, e.g. Gaspar Sanz and the manuscript conserved by Antonio Martín y Coll.

The name in England, France, Italy and Spain

The 'early' Folia is sometimes called Folías españolas while the 'later' Folia might be indicated as Folías italianas. Derived from the Tuscan term "Folle" (meaning empty- headed) the title Follia (with double LL) is used by many Italian composers. Because every variation is regarded as an independent unity, the plural form Folias is not unusual either. In Spain the old spelling lacked accents so in the modern Spanish spelling the way to indicate the tune correctly is "folía" with the accent on the i.

The English word Folly has roughly the same meaning as the Tuscan term. However, oddly enough, in England the Folia became known under the title Farinelli's Ground, with various spellings of the name Farinel, named after an Italian violinist who went to Germany and England and who contributed to the popularity of the tune in England, although indications as 'Joy to Great Caesar', 'The King's Health', and 'The Loyal Health' might also indicate the Folia-theme.
In France the structure and its variations became known as Folies d'Espagne, with reference to its presumed origin.
In the Scandinavian countries the Folia-theme is closely linked to the folkmusic (fiddle) tradition.

Scandinavian Folias

In Finland an extended version of the Folia-theme is known as Lampaanpolska (translation in English: 'The Sheep's Polka' or 'Mutton Dance', in German: 'Schafspolka'). In Sweden the closest translation of the Folies d'Espagne is known as fiol i spann (meaning literally: fiddle in span or violin in a bucket, although the Swedish word 'fiol' also means the flower violet) but there are many derivations of the Folia very popular in Sweden under the name Sinclairsvisan. 'Visa' in Swedish means roughly the same thing as 'song' in English. 'Sinclair' is derived from Malcolm Sinclair, a Swedish diplomat, who was murdered on his way home from Turkey 1739 on orders of the Russian government. The original 90 verse text was written by Anders Odel (1718-1773) but there are lots of variants on the original text, and many of them are of a political nature. The Swedish poet Carl Michael Bellman (1740-1795) also set words to the La Folia melody, no doubt helping along its spread in Sweden.
In Norway, the La Folia tune is usually called 'I Roselund i Sagas Hal'. A number of Norwegian songs, ballads, and lullabies are set to this tune. Norway also has a 'Sinclair vise' (variously Sinclar or Zinclar), but it's about a different event, and uses a different melody.

Another detail of a dutch manuscript as part of the family-archive Bosch, van (von) Rosenthal and relatives dated back to the year 1695. © Rijksarchief Gelderland, used with permission

Corelli's variations