Masquerade vs. Fancy Dress Balls

Masquerade Ball at the Ritz Hotel, Paris Raimundo de Madrazo 1909

This painting proves that people really have a good time when they dress up in costume and dance. Look at those dancers chasing each other through the rooms and knocking over chairs!

I suppose that the title of the painting is incorrect, since no one here is wearing a mask. Strictly speaking, masquerades involve masks, fancy dress balls do not involve masks. Rudolph Radestock explains it:

There is one class of balls which forms a distinct series, and takes the form of Masquerades, Fancy Dress Balls, and Fancy Calico Balls. The first-named indicates that the persons attending such assume all kinds of grotesque imitations, so as to hide their persons and faces; in fact, make recognition almost impossible. This class of balls occurs most frequently on the Continent, and affords a great deal of amusement, and, as a rule, are highly enjoyable.

A Fancy Dress Ball permits you to assume a character of any description, or any nationality you like, but you must expose your features. In both kinds, when inscribing your engagements on your programme, you don't insert your name, but simply (if, for instance, as a masked party, you represent a bear) you might write "bear;" and if in Fancy Dress, representing a hussar, you write "hussar." It must be observed that at Masquerades the masks are taken off at twelve o'clock.

Calico Balls have been introduced, and the meaning of such simply is that your entire dress must be made of calico. Very effective costumes can be furnished by introducing or imitating a pack of cards, viz., four Queens, and four Knaves, or Kings, &c. (Rudolph Radestock. The royal ball-room guide and etiquette of the drawing-room, containing the newest and most elegant dances and a short history of dancing. London: W. Walker and Sons [pref. 1877] p. 36-37)