The Royal Order of the Seraphim (Swedish: Kungliga Serafimerorden; Seraphim being a category of angels) is a Swedish order of chivalry created by King Frederick I on 23 February 1748, together with the Order of the Sword and the Order of the Polar Star. The order has only one class with the dignity of Knight (Member for women and Member of the Cloth for clergymen), and is the foremost order of Sweden.
The three above-mentioned Orders together with the Order of Vasa form the Orders of His Majesty the King (Swedish Kungl. Maj:ts Orden). A Swedish Knight of the Order of the Seraphim is not referred to as a Knight of the Seraphim, but rather as a Knight and Commander of the Orders of His Majesty the King (Swedish: Riddare och Kommendör av Kunglig Majestäts Orden). This form is used because the Swedish word orden is an old plural form which indicates that a knight has to be a Commander Grand Cross or Commander of at least one of the other Swedish Orders. Foreign Knights are for the greater part Knights of the Order of the Seraphim. A Knight of the Order may be styled "Herr" + surname, which used to be the formal style for Swedish secular Knights (untitled high-ranking noblemen) appointed by the Swedish King, a practice that ceased in the 17th century.
When originally instituted the knights of the Order were required to supervise the major hospitals and mental asylums in Sweden, and in particular, the Seraphim Hospital, which was a major hospital in Stockholm until it was closed in 1980. This requirement would die out as boards of physicians and other professionals made such supervision by the Knights of the Seraphim anachronistic during the course of the 19th century.
As part of the reorganization of Swedish orders in 1975, appointments of Swedish citizens to the various orders ceased and conferrals were restricted to foreigners (the last non-royal Swedish holder was Sten Rudholm). Likewise, the Order of the Seraphim was restricted to foreign heads of state and equivalents. In 1995, the law was revised and conferrals upon members of the royal family were allowed. On 20 December 2022, the Swedish Government published a new regulation that repealed the 1974 regulation, and once again opened the Royal Orders to Swedish citizens again, to be in effect from 1 February 2023.