The unit was not a fantasy, but it was also not a part of the army of King Joseph.
It is now clear that Aaron Martinet made a mistake : he identified a unit called "lanceros de la Mancha" as one of Jospeh's army. It was in fact a "Bourbon" Spanish unit, raised by the Junta and bearing the monogram of Ferdinand VII on their shabraques.
Knötel (the Elder) amplified Martinet's error (managing also to "create" 7 imaginary regiments of Josephine cavalry !) and, until more recent research led by Dr. Luis Sorando y Muzŕs, most unifomologists have followed Knötel.
From Knötel, after Martinet :
picture
Here is a contemporary notice about the unit, fighting with Juan Martín Díez ("El Empecinado") near Cuenca (July 1811) :
link
See
.
"El enigma de los lanceros de la Mancha"
Juan J. Sańudo, Luis Sorando & Henry Claude Achard
Researching & Dragona nş 2, paginas 47-51
"Les sources classiques sur l'armée de Joseph Napoléon roi d'Espagne : une analyse critique"
Luis Sorando & Massimo Florentino (trans.)
Soldats Napoléoniens Hors-série nş 1, avril 2003
"La cavalerie de ligne espagnole de Joseph – 1čre partie : les chasseurs ŕ cheval"
Luis Sorando Muzŕs, Patrice Courcelle (illus.) & Massimo Fiorentino (trans.)
Soldats Napoléoniens n° 5, mars 2005
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There was a squadron sized unit of lancers in Joseph's army, usually identified as the "lanceros de Sevilla", under the command of colonel Aguado. They were trained by the 7th (ex- Vistula) lancers, and wore a blue trimmed chamois uniform modelled after the uniform of thier mentors.
See
.
Spanish Armies of the Napoleonic Wars (1812-1815)
René Chartrand & Bill Younghusband (illus.)
Osprey Men-at-Arms nş 334, 1999
"El primer regimiento de lanceros espańoles, 1811-1813"
Luis Sorando
Researching & Dragona – nş 4, 48-54
Alejandro Aguado : militar, banquero, mecenas
Armando Rubén Puente
Madrid : Editorial Edibesa, 2007
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Back among the "Bourbon" Spanish, there was another unit of lancers that operated in the New Castille-La Mancha area, the "lanceros de Castilla", with D. Julián Sánchez ("El Charro") as their commander. A rather larger unit (perhaps fielding up to 750 mounted men), they were uniformed as hussars.
Here is a image drawn from life by Denis Dighton in 1812 :
picture