Neither did I! Found this info here
Here is part of the article:
Women Knights in the Middle Ages
Were there women knights in the Middle Ages? Initially I thought not, but further research yielded surprising answers. There were two ways anyone could be a knight: by holding land under a knight's fee, or by being made a knight or inducted into an order of knighthood. There are examples of both cases for women.
Female Orders of Knighthood
The Order of the Hatchet
There is a case of a clearly military order of knighthood for women. It is the order of the Hatchet (orden de la Hacha) in Catalonia. It was founded in 1149 by Raymond Berenger, count of Barcelona, to honor the women who fought for the defense of the town of Tortosa against a Moor attack. The dames admitted to the order received many privileges, including exemption from all taxes, and took precedence over men in public assemblies. I presume the order died out with the original members.
Here is a description taken from Ashmole, The Institution, Laws, and Ceremony of the Most Noble Order of the Garter (1672), Ch. 3, sect. 3:
"The example is of the Noble Women of Tortosa in Aragon, and recorded by Josef Micheli Marquez, who plainly calls them Cavalleros or Knights, or may I not rather say Cavalleras, seeing I observe the words Equitissae and Militissae (formed from the Latin Equites and Milites) heretofore applied to Women, and sometimes used to express Madams or Ladies,though now these Titles are not known.
"Don Raymond, last Earl of Barcellona (who by intermarriage with Petronilla, only Daughter and Heir of King Ramiro the Monk, united that principality to the Kingdom of Aragon) having in the year 1149, gained the City of Tortosa from the Moors, they on the 31 of December following, laid a new Siege to that place, for the recovery of it out of the Earls hands. The Inhabitants being a length reduced to gread streights, desired relief of the Earl, but he, being not in a condition to give them any, they entertained some thoughts of making a surrender. Which the Women hearing of, to prevent the disaster threatning their City, themselves, and Children, put on mens Clothes, and by a resolute sally, forced the Moors to raise the Siege.
"The Earl, finding himself obliged, bythe gallentry of the action, thought fit to make his acknowlegements thereof, by granting them several Privileges and Immunities, and to perpetuate the memory of so signal an attempt, instituted an Order, somewhat like a Military Order, into which were admitted only those Brave Women, deriving the honor to their Descendants, and assigned them for a Dadge, a thing like a Fryars Capouche, sharp at the top, after the form of a Torch, and of a crimson colour, to be worn upon their Head-clothes. He also ordained, that at all publick meetings, the women should have precedence of the Men. That they should be exempted from all Taxes, adn that all the Apparel and Jewels, though of never so great value, left by their dead Husbands, should be their own.
"These Women (saith our Author) having thus aquired this Honor by their personal Valour, carried themselves after the Military Knights of those days." Jeanne Hachette, who fought to repel a Burgundian assault on the town of Beauvais in 1472. The King exempted her from taxes, and ordered that, in an annual procession to commemorate the event, women would have precedence over men. This story seems to be a carbon copy of the Order of the Hatchet story...
In Italy, the Order of the glorious Saint Mary, founded by Loderigo d'Andalo, a nobleman of Bologna in 1233, and approved by pope Alexander IV in 1261, was the first religious order of knighthood to grant the rank of militissa to women. This order was suppressed by Sixtus V in 1558.
In the Low Countries, at the initiative of Catherine Baw in 1441, and 10 years later of Elizabeth, Mary and Isabella of the house of Hornes, orders were founded which were open exclusively to women of noble birth, who received the French title of chevalière or the Latin title of equitissa. In his Glossarium (s.v. militissa), Du Cange notes that still in his day (17th c.), the female canons of the canonical monastery of St. Gertrude in Nivelles (Brabant), after a probation of 3 years, are made knights (militissae) at the altar, by a (male) knight called in for that purpose, who gives them the accolade with a sowrd and pronounces the usual words.
In England, ladies were appointed to the Garter almost from the start. In all, 68 ladies were appointed between 1358 and 1488, including all consorts. Though many were women of royal blood, or wives of knights of the Garter, some women were neither. They wore the garter on the left arm, and some are shown on their tombstones with this arrangement. After 1488, no other appointments are known, although it is said that the Garter was granted to a Neapolitan poetess, Laura Bacio Terricina, by Edward VI. In 1638, a proposal was made to revive the use of robes for the wives of knights in ceremonies, but it came to nought. (See Edmund Fellowes, Knights of the Garter, 1939; and Beltz: Memorials of the Order of the Garter).
Unless otherwise noted, all the above is from the book by H. E. Cardinale, Orders of Knighthood, Awards and the Holy See, 1983. The info on the order of the Hatchet is reproduced elsewhere as well, e.g., a Spanish encyclopedia. I have seen the order of glorious Saint Mary discussed elsewhere, but without mention of women. I have yet to identify the orders of the Hornes family.
Women in the Military Orders
Several established military orders had women who were associated with them, beyond the simple provision of aid. The Teutonic order accepted consorores who assumed the habit of the order and lived under its rule; they undertook menial and hospitaller functions. Later, in the late 12th century, one sees convents dependent on military orders are formed. In the case of the Order of Saint-John (later Malta), they were soeurs hospitalières, and they were the counterparts of the frères prêtres or priest brothers, a quite distinct class from the knights. In England, Buckland was the site of a house of Hospitaller sisters from Henry II's reign to 1540. In Aragon, there were Hospitaller convents in Sigena, San Salvador de Isot, Grisén, Alguaire, headed each by a commendatrix. In France they are found in Beaulieu (near Cahors), Martel and Fieux. The only other military order to have convents by 1300 was the order of Santiago, which had admitted married members since its foundation in 1175. and soon women were admitted and organized into convents of the order (late 12th, early 13th c.). The convents were headed by a commendatrix (in Spanish: commendadora) or prioress. There were a total of six in the late 13th century: Santa Eufenia de Cozuelos in northern Castile, San Spiritu de Salamanca, Santos-o-Vello in Portugal, Destriana near Astorga, San Pedro de la Piedra near Lérida, San Vincente de Junqueres. The order of Calatrava also had a convent in San Felices de los Barrios.
and thirteenth centuries,' Studia Monastica 1987 (vol. 29).
Medieval French had two words, chevaleresse and chevalière, which were used in two ways: one was for the wife of a knight, and this usage goes back to the 14th c. The other was as female knight, or so it seems. Here is a quote from Menestrier, a 17th c. writer on chivalry: "It was not always necessary to be the wife of a knight in order to take this title. Sometimes, when some male fiefs were conceded by special privilege to women, they took the rank of chevaleresse, as one sees plainly in Hemricourt where women who were not wives of knights are called chevaleresses."
I could find no trace of any title bestowed on Jeanne d'Arc. Her family was made noble, with nobility transmissible through women, which was quite unusual. She did ride a horse and dress up in armor, but she did not wield a sword and never killed anyone, but rather grasped her banner pretty tightly.
See also the Nine Worthy Women (les neuf preuses).