The Knights of Malta (name used since 1530) are a secular, Catholic order; according to the Catholic Encyclopaedia, "the most important of all the military orders."
Gerald (or Girard) was the founder, his position attested by The Bull of Paschal II, dated 1113. Unlike the Templars who were military, the early Hospitallers had no military role.
They became the Knights of Rhodes after fusion with the remaining Knights Templar in the early 14th c.
Because of the depredations by Muslim pirates, the Knights became corsairs, not only to fight the pirates, but to make reprisals on Turkish merchantmen and pillage important Muslim ports such as Alexandria and Smyrna.
Skipping to the present, there are now four priories, three in Italy and one in Bohemia. They still have commanders and several classes of knights, all of whom wear the eight-pointed star of the Order. They own the Convento S. Maria del Priorato in Rome, where many of their archives are housed. There are tombs of some of the Knights in the Convent church.

Catholic Encyclopaedia, Hospitallers

The 'song' in the Bothy ballads is not a Masonic song; probably a street ditty.