Mallett apparently wrote one of best works on this topic, and one that has not been surpassed since. Italian mercenaries have a bad reputation: plumed cowards who refused to close to battle, who switched sides at will, and who ravaged the countryside. Mallett goes beyond the ideological commentators (Machiavelli and various 19th century Italian historians with axes to grind), to get at the mercenaries as they were.

What he reveals is the creation of one of first standing armies in Europe, a disciplined combined arms military system that influenced the continent and was only defeated through political division. Italian mercenaries went from barely organized bandit groups in the 12th century, to independent sovereign powers in the 13th, to key assets of Italian city states in the 14th. They were couragous and vile in turn, but also dedicated and trained professionals with an advanced grasp of tactics, logistics, and weaponry.

Mallett writes exceptionally clearly for an academic, avoiding many of the worst tropes of high theory. His historical account is leavened with descriptions of battles and characters, and while it may be difficult to keep all the characters apart in-mind, I can think of no superior work for this topic.