The noble estate was never abolished in Sweden, but the privileged position has been weakened step by step from 1680 and forth. The political privileges were practically abolished by the reformation of the Riksdag of the Estates in 1864, and the last rights of precedence to certain governmental offices were removed in the 1920s. By then also the last taxation privileges were abolished.
The privileges in Sweden are nowadays limited to a protection of some additional part of the heraldic arms: the helm with open visor and the crowns marking the honor. In practice also the surnames are protected.
In contrast to the United Kingdom and the Benelux countries, no hereditary titles or honors have been granted since the 1900s.
The nobility in Sweden (and Finland) dates back to 1280 when it was agreed that magnates who could afford to contribute to the cavalry with a horse-soldier were to be exempted from tax - at least from ordinary taxes - as the clergy already had been. The archaic term for nobility, "frälse", includes also the clergy while referring to their exemption from tax.
The background was that the old system of a leiðangr fleet and a king on constant travels in the realm became outmoded and in need of replacement. The crown's court and castles were now to be financed through taxes on land.
Soon it was also agreed that the king should govern the realm in cooperation with a Privy Council (or State Council) where the bishops and the most distinguished among the magnates (i.e. the most prominent contributors to the army) participated. When troublesome decisions were necessary all of the frälse was summoned to diets.
The Swedish nobility had no hereditary fiefs. In case they were appointed to a castle of the crown's then their heirs couldn't claim their civil or military authority. The lands of the magnates who constituted the medieval nobility were their own and not "on lease" from a feudal king. If they by own means (including the suffering of the local peasantry) build a castle, and financed its troops, then the castle was theirs but the troops, of course, expected to serve as a part of the realm's army.
For exstended periods the commander of Vyborg at the border to Novgorod/Russia did in practice function as a Margrave, keeping all the crowns incomes from the fief to use for the defense of the realm's eastern border. But despite the heavy German influence during the medieval age the elaborate German system with titles as Lantgraf, Reichsgraf, Burggraf & Pfalzgraf was never applied.Medieval nobility