Widely used in Europe, especially in Eastern Europe, but also in English-speaking countries, from Greek "wisdom".
A very popular name in the 1841 Census of Aberdeenshire which has a number of different spellings, based on phonetic recording. These include Sofia, Sophea, Sopheea and Sophiah. The latter three spellings are extremely rare but care must be taken when looking at older records.
The Scottish Gaelic name Beathag/Bethoc can be Anglicized as Sophia or Rebecca so, in Gaelic areas of Scotland, these names and Beatrice/Beatrix are therefore classed here as lesser synonyms. A correspondent [ES2] has confirmed that, in her family tree, a girl baptized as "Bethoc" in Inverness-shire was thereafter always recorded as "Sophia".
GB reports the spelling Suffia in an Episcopal Church record in Banffshire. This spelling probably will not be found by Soundex searching.