When the Spanish adopted the colunella (the first of the mixed pike and shot formations), they used small groups of sword and buckler men to break the deadlock of the push of pike, as the Swiss and Germans used halberdiers, comparable to the role of the German Doppelsöldner during the same period.
This title was relevant for the Landsknechts, because a certified "master of the long sword" wielding the Zweihänder was entitled to twice the pay of a normal soldier (Doppelsöldner).