Word-initial ff

The digraph at the beginning of a word is an anomalous feature, in lower case, of a few proper names in English. In that setting it has no phonetic difference from, and has been explained as a misunderstanding of palaeography. In other words,, which is "Latin small ligature ff", a stylistic ligature from Unicode, available now in some Latin script fonts, represented in certain traditional handwriting styles the upper case.
In Spanish orthography, on the other hand, word-initial had a phonetic meaning for several centuries.

In English

Mark Antony Lower in his Patronymica Brittanica called this spelling an affectation. He stated that it originated in "a foolish mistake concerning the ff of old manuscripts, which is no duplication, but simply a capital f." Later in the 19th century the palaeographer Edward Maunde Thompson wrote from the British Museum:
The replacement of manuscript word-initial by is now a scholarly convention.
Usage in names such as Charles ffoulkes and Richard ffrench-Constant persists. The initial in Welsh spelling of imported proper names has been attributed to the standing of as part of normal Welsh orthography. Citing Trevor Davenport-Ffoulkes, H. L. Mencken wrote in a supplement to The American Language that "The initial Ff is sometimes written ff, but this is an error." David Crystal cites both Welsh-derived proper names, such as Ffion, and English-derived names such as Ffoulkes.

In Spanish

It has been argued that word-initial was used in written Spanish around 1500, to indicate the phonetic difference between an f-sound and an aspirated h. It can be observed to have come in strongly for Spanish spelling during the 13th century. The actual pronunciation was dynamic, with the aspiration being dropped from the time when Madrid became the Spanish capital. The word-initial spelling convention lagged behind current phonetics, providing a way of tracking pronunciations after they had become obsolete.