Below is a little insight into the protocol of the Hunt during the reign of Napoleon 111 and Empress Eugenie. Jane Thorn de Pierres is mentioned often for her riding prowess. That means she got to wear the formal hunt gear and buttons. It looks rather tight and restrictive to be riding sidesaddle in.

When the Empress went riding she was always attended by an equerry and by Baroness de Pierres, a fine horsewoman, of whom we spoke in an earlier chapter.* Her Majesty’s first piqueur, who had served Louis Philippe, like so many of the stable officials and domestics, only followed her at reviews and hunts. She had four favourite horses, Phoebus, Langiewicz, Elastic, and Chevreuil, the last- named being a capital hunter.

Green was the predominant colour of the uniform and the liveries of the Hunt. The former had a collar and cuffs of crimson velvet, and silver buttons bearing gold stags. There was also no little silver embroidery and braid. Further, three-cornered hats were worn, those of the Emperor and Empress having their brims edged with white plumes. The various officers carried long hunting-knives.

The Empress’s habit was of green cloth with trimmings of crimson velvet, gallooned and embroidered with gold. In accordance with the custom of former reigns, whenever the Emperor granted anybody the right to follow the Hunt and wear its uniform, he sent the favoured individual the necessary buttons for the costume.

…Members of the company were often called “the Buttons.” The Emperor’s aides-de-camp and orderlies belonged to the Hunt by right, and any civilian officers of the Household who applied for the buttons usually obtained them. The Great Chamberlain, the Duke de Bassano, and the Great Master of Ceremonies, the Duke de Cambaceres, wore the uniform, as did also Prince Napoleon, Prince Murat, several foreign princes and diplomatists, such as Lord Cowley, Prince Metternich, and Baron Budberg.

Marshal de Castellane’s daughter, the sprightly and witty Marquise de Contades, who, by her second marriage with a captain of the Artillery of the Guard, became Countess de Beaulaincourt-Marles, and who, in conjunction with Princess Mathilde, had kept house for Napoleon during his presidency days at the Elysee Palace, was, like that skilful horsewoman the Baroness de Pierres, one of the few ladies to whom the privilege of wearing the uniform was accorded. Among well-known men who enjoyed it were
Dukes de Morny, Persigny, Caumont-Laforce, and Vicence, the Marquis de L’Aigle, Marshal MacMahon, Count Nieuwerkerke, the Aguados, Achille Fould, Baron Henri de Poilly, MM. d’Offemont, de Montgermont, and Edouard Delessert.

The liveries of the huntsmen, whippers-in, and kennelmen of the Venery partook of the character of the uniform, but the embroidery was somewhat less rich, and white metal buttons, in some instances, took the place of the silver ones. The costumes, which were in most respects of an eighteenth-century style, suggestive of the garb of Captain MacHeath and Claude Duval, encountered no little criticism and ridicule in many quarters, but they were undoubtedly picturesque, and not much more absurd or extraordinary, perhaps, than the English “pink.”