The Black Band was created as the Black Guard in 1514 by George, Duke of Saxony, to fight for his claims in East Frisia against Edzard I, Count of East Frisia, in what was to become known as the Saxon feud.
It is not clear whether the band was newly founded or a continuation of the Great or Black Guard that was founded in 1488 by Landsknechts formerly in Imperial service with Maximilian in Flanders. It fought in Northern Germany and Denmark, often against rebellious peasants, until its defeat at the Battle of Hemmingstedt. It is possible that at least some Fähnlein of the Black Guard survived during these fourteen years and were part, if not core, of the new formation.
This Black Guard took part in the campaign in East Frisia in 1514 and devastated large parts of it in the process. When the participation of George of Saxony in the Saxon Feud ended in 1515 at the mediation of Charles II, Duke of Guelders and Francis I of France, Charles of Guelders hired them and led them in support of Francis to Italy, where they entered French service. There they joined an existing contingent of 12,000 Landsknechts in French service, originally drafted for a planned invasion of England under the Yorkist pretender Richard de la Pole, that was aborted after the Anglo-French peace treaty of St Germain-en-Laye in 1514. Many of these Landsknechts were originally sent "on loan" to the French by Maximilian between 1512 and 1513 for service in Italy, notably at Brescia and Ravenna, and had defied his recall to Imperial service. Some of the members of the Black Band also chose not to enter French service and heed that recall.
The distinction between both contingents gets lost and most sources call the whole French Landsknecht contingent the "Black Band" or "Black Legion" at the time of the Battle of Marignano.
The full Landsknecht contingent of Francis I. army in 1515 was initially 17,000 men strong, composed of 12,000 pikemen, 2,000 arquebusiers, 2,000 two-handed swordsmen, and 1,000 halberdiers. Landsknecht contingents are organized in companies or Fähnlein of up to 500, with actual numbers often being lower than the nominal full strength.