Louis XIV | letter signed, giving military orders to the Duc d'Aumont, commanding the army on the coast. 1667

Louis XIV

Letter signed ("Louis"), to Antoine d'Aumont de Rochebaron, Marshal of France and Duc d'Aumont, at the start of the "War of Devolution" (Guerre de Dévolution), 12 June 1667

in French, mainly in code (incompletely deciphered), giving military orders to his Lieutenant General commanding the army on the sea coast, acknowledging his report on the conduct of the troops under his command in the region of Birgues, informing him about his plans for the entire army (in numerical cipher), and ordering him to drop everything to march immediately with his infantry and two or three hundred horses, [i.e. to come to Flanders] with another General (identified in code, but possibly Henri Turenne), assuring him that the troops will be regularly supplied with provisions and that every fortnight their wages will be paid regularly by the Treasury   

11 pages, small 4to, with integral address leaf, two fine impressions of red wax seals and remains of silk ties, original pale blue silk ribbon, early annotations in another hand at the head of the first page, Avesne (Pas-de-Calais), 12 June 1667

In May 1667, Louis XIV invaded the Spanish Netherlands and Franche-Comte with a hundred thousand troops. Both provinces belonged to Spain, but Louis XIV claimed them under the pretext that they had "devolved" to him as part of the dowry obtained through his marriage to Maria Theresa of Spain. Within three weeks, Louis's general Henri Turenne had overrun the whole of Flanders (dubbed the "Promenade militaire"), but the next year he had to retreat in the face of English and Dutch resistance.

Of the 234 lines of text, no fewer than 193 are wholly or partly in cipher. The system used appears to be a variant of the celebrated "Great Cipher", invented by the father and son Antoine and Bonaventure Rossignol. Its main principles were worked out at the end of the 19th century, but not all the details present here have been deciphered.

PROVENANCE:

Sotheby's, 24 June 1993, lot 497