The Order of the White Scarf was originally created as an award in the Principality of Ansteorra in March of A.S. XIII (1979). It was intended to provide recognition for excellence in the growing population of rapier fighters in the principality. When Ansteorra became a kingdom in May of A.S. XIV, the order was released from the parent kingdom of Atenveldt to Ansteorra for its continued use. At that time there were some 40 or 50 rapier fighters in Ansteorra, and a few handfuls scattered throughout the rest of the Known World.
In the Renaissance a white scarf was worn as a badge of military rank. The only picture I've ever seen shows it worn as a baldric, left shoulder to right hip.
Obviously this would be unacceptable in an SCA context, so a much smaller version, worn only about the shoulder, was designed. (Cyrano de Bergerac was the source of the original idea.) There is also a picture of Sir Walter Raleigh wearing a white scarf tied just above his left elbow (see above). I’m not sure if this was also a military badge, or if it is a lady’s favor, but the style of wearing White Scarves in this fashion is becoming more common.
The Order continued to add new members as the rapier community in Ansteorra grew. It became traditional for the Crown to hold meetings with the Order to discuss potential new members, as well as issues of general interest to the rapier community, such as rules changes or inter-kingdom events. The Crown is not required to hold these meetings, or to take any action based on the opinions expressed there, but they generally do. (The Ansteorran Crown has granted their Order of the White Scarf the Right of Consultation, which requires the Crown to consult with the order, but it is still not obligated to take any action based on that consultation). It is also traditional for the White Scarves in particular, and the rapier community as a whole, to look to the Queen much more than to the King. This is based partly on the fact that several prominent members of the White Scarves have Elizabethan personas, and partly on a "Three Musketeers" flavor from the days when the general belief was that the SCA’s time period extended to 1650. The Queen's Champion in Ansteorra is traditionally decided by a rapier list; most of the other kingdoms that have rapier combat also have a Queen's Rapier Champion, or something similar.
In October of A.S. XXI (1987), the kingdom of the Outlands signed a treaty with Ansteorra to create their own Order of the White Scarf. Since that time, there have been some 30 or 40 members added.
In June of A.S. XXVII (1992), the Kingdom of Trimaris signed a treaty with Ansteorra and the Outlands to become the third kingdom in the Known World to have an Order of the White Scarf. At about the same time, the Kingdom of the East debated creating their own White Scarf, but decided against it.
In the Spring of A.S. XXVII (1994), Atenveldt and An Tir also joined the White Scarf treaty. Their addition to the treaty was done entirely by mail; previously, the groundwork had been done by mail, but the actual signing was done at an interkingdom event. In this case, there wasn't an interkingdom event conveniently available (Estrella war having just passed, and Pennsic being several months away), so it was decided not to wait.
The East Kingdom has the Order of the Golden Rapier, which was briefly allied with the White Scarves, but the treaty was abrogated by their Crown in October of 1996.
In January of AS XXX (1996), Atlantia joined the White Scarf Treaty, followed by Caid in November AS XXXI (1996). In October of AS XXXII (1997) The new kingdom of AEthelmearc joined the White Scarf Treaty, and in January of AS XXXII (1998) the new kingdom of Artemisia joined the White Scarf Treaty. In July of AS XXXVII (2002), the new Kingdom of Lochac joined the White Scarf Treaty. In December of AS XXXIX (2004), the new Kingdom of Northshield joined the White Scarf Treaty. In May of AS XLII (2007), the Kingdom of the West established the Western Order of the White Scarf, bringing the total number of kingdoms awarding a White Scarf to twelve. While functionally the same as the White Scarf in other kingdoms, internal political considerations prevented the West from signing the White Scarf Treaty. Instead, they received separate “permission to conflict” letters from the other White Scarf kingdoms.
In March of AS XLIII (2009) Ansteorra celebrated the thirtieth anniversary of the Order of the White Scarf.
In June of AS L (2015)the new kingdom of Avacal joined the White Scarf Treaty.
With the creation of the Order of Defense peerage, several kingdoms have decided to close their Order of the White Scarf. Artemisia closed theirs on March 7th, AS 49 (2015), An Tir, Northshield, the West Kingdom, Caid, Lochac and Avacal have closed theirs as well.
Most of the Orders carry a Grant of Arms, and it is customary in most kingdoms that holders of the White Scarf are addressed by the title "Don" or "Dona" There was a major discussion in the Heralds' Office in A.S. XXVI (1991) about the use of that title. In 1980, a decision had been made at the Laurel level that the title "Don" was reserved for knights. This decision was never disseminated to the general populace and, as far as I know, only two knights ever used it. The result of the 1991 discussion was that "Don" could be used by anyone with an AoA or above, which is more in keeping with historical practice. (Just to complicate matters, there has been a group of rapier fighters in the East Kingdom using the title "Don" as part of their ranking structure, the "gold cords." This group is based upon the English Masters of Defence, but has no "official" status within the East Kingdom.)
White Scarves will sometimes take "cadets," who are special students of that particular Don (much like squires). Cadets traditionally wear a red scarf (*) either tied about their upper left arm or worn about the left shoulder. Cadets are occasionally guilty of conspiracies for good-natured teasing of the White Scarves.