A bigwig is an important person, someone of a high status. The OED says this is because “of the large wigs formerly worn by men of distinction or importance.”
The term ‘bigwig’ was first recorded in 1703 in a weekly journal called English Spy. The next time it’s seen in print is G. Selwyn’s 1781 Letters in 15th Rep. Hist. MSS. Commission:
“A new point of discussion for the lawyers, for our big wigs, for their Lordships.”
This emphasizes the use of the term in relation to the British judiciary, who then wore wigs in court. And still do.
The word ‘wig,’ for the hairpiece, was first recorded in the 1600s as a short form of ‘periwig,’ according to the Oxford English Dictionary. ‘Periwig’ and ‘peruke’ came into English in the 1500s as words describing a hair piece, and both were derived from a Middle French word spelled perrucque or perruque.
According to one source, the fashion for wigs was begun by the Bourbon kings of France. Louis XIII (1601 – 1643) went bald early in life and began wearing a wig. Ostentation was the order of the day and over time the wigs became bigger, often to the point of absurdity and needing scaffolding. By the middle of the century, and especially during the reign of Louis XIV, The Sun King, wigs were virtually obligatory for all European nobility and ‘persons of quality.’
Wigs were expensive to purchase and to keep in condition and were thus the preserve of the powerful and wealthy. The fad grew to the point where it became fashionable for people to shave their heads and replace their hair with wigs; in this way they could sport a style they might not be able to naturally grow. It was seen as a triumph of man’s ingenuity over nature.
This fad faded away as quickly as it had come with the advent of the top hat, however it lives on in the large ceremonial wigs seen in the British courts.
These days, if wigs were still “in,” they would probably be streaked red or green or blue, which would perhaps be more interesting.