This time frame from 1789-1825 is actually several different sub-periods. The first, 1789-1799, the period of The French Revolution, is a sharp transition period. The second 1800-1815 is the time of the French Consulate and Empire, and is a stable Neo-classical period. 1815-1825 is the late Neo-classical period that shows a gradual shift towards the Romantic style
Dress in The French Revolution
Dress during this period goes through a massive shift. Late 18th Century women's dress collapses from it's padded and puffed look to a thin, often translucent silhouette. As the French Revolution progressed, different women's styles were adopted that appeared to have reference to the revolutionary politics, social structure and philosophy of the time. In the early 1790's, for example, the "English" or man-tailored style was favored as it hinted towards the leanings of constitutional monarchy. There was a brief fashion for plain dresses in dark colors during the Terror of 1792, but when the Directory took over French fashion again went wild, trying out "Rousseauesque" fashions in "Greek", "Roman", "Sauvage" and "Otaheti" (Tahitian) styles.
The Psudo-"Greek" look proved most popular and was adopted as the standard style in Europe in the late 1790's
Costume for a ball "a la sauvage", 1796. 2. "Greek" style dress, 1797.
A dress of the male style in vogue between 1780-95
Men's
While Men's Costume in the 1790's also becomes thinner in line, it separates it's style from women's dress by beginning to lose nearly all forms of surface decoration, lace and bright color, as "irrational" and feminine effluvia. This change is slow, but it completely alters men's dress by the mid 19th Century into dull dark uniform dress.
Other major changes include the adoption of trousers from the dress of sailors and the urban proletariat of the French Revolution, the passing of the fashions for wigs and hair powder, and the (very temporary) demise of the corset.
The bonnet is invented as a hat that is meant to look like a Greek helmet, but it quickly is altered in style out of all resemblance to the original.
Men's dress also keeps on a fairly steady course towards increasing dullness. Fashion magazines continue to push men's dress towards foppish extremes, but men who actually count in the fashionable world tend to push for plainer styles. Beau Brummell, the leader of male sartorial fashion in England in this period was noted for wearing only black with a white shirt for formal evening wear, a marked departure from the style of the previous century. Tubular and fitted trousers also move from a radical fashion statement to everyday wear for most men of the upper classes.
Men's clothing in this era becomes less and less adventurous in style. The few outlets for male fashion expression (boots, hats, collars and neckties) therefore go to extremes. Neckties in this period were especially important
France 1800 in Max von Boehn's
1822 Vienna from Max von Boehn's 
Bonnets from "Wiener Zeitschrift", Vienna, 1820 in Max von Boehn's
