Werner von Urslingen Werner von Urslingen ( Italian : " Guarnieri d ' Urslingen " or " Duca Guarnieri " ; c . 1308 – 1354 ) was a German mercenary . He was born at Irslingen , in Irslingen Swabia , a member of the family of the dukes of Urslingen , and probably a descendant of the dukes of Spoleto . In 1338 he fought for the Republic of Venice against Mastino II della Scala of Verona . After the end of the conflict he entered the Compagnia di San Giorgio , financed by the Veronese and led by Lodrisio Visconti . He took part in the battle of Parabiago . From 1342 he was at the service of the Republic of Pisa in the war against Florence , whose troops were led by Malatesta III Malatesta . Afterwards he collected a troop of adventurers under the name " Great Company " , and with which he plundered Tuscany , Umbria , Romagna . There he supported Francesco Ordelaffi against the Papal States . Here he was bribed by his enemy , Malatestino Malatesta of Rimini , to help him in his feud with Ferrantino Malatesta . In 1343 he was hired by Taddeo Pepoli of Bologna for a very large sum , to fight against Obizzo III d ' Este of Modena ; he however switched to the Este side and moved to ravage several cities , including Correggio . The company was subsequently expelled from the Ferrara area , and von Urslingen returned to Germany with parts of his troops . In 1347 he returned to Italy . He then entered the service of Louis I the Great , king of Hungary and Poland , whom he assisted to obtain possession of Naples . von Urslingen ' s troops defeated Louis , Prince of Taranto ( Joan ' s husband ) near Naples , and Louis of Hungary was able to enter Naples ; the following year , however , Werner was accused of collaboration with Joan , and arrested . After having been freed , he entered the service of the Caetani of Fondi with 3 , 000 men , to attack the Orsini at Supino . In 1348 he sacked and destroyed Anagni : this spurred Perugia and other communes to muster an army against him , and Werner , whose troops had also been struck by plague , was forced to retire . He then passed under the Papal States , for which he conquered several territories , and then to Joan of Naples , whom he helped to return in Naples . In 1349 , after a period of operations in Apulia ( of which he was named viceroy ) , he was ambushed by the voivoda of Transylvania , Stephen Laczkfy and defeated . Werner mustered an army of 3 , 000 Hungarian , German and Neapolitan knights and 2 , 000 Lombard infantry to counter Stephen , defeating him before Naples . In 1350 he allied with Giovanni di Vico to ravage the Papal fiefs in northern Latium . In the same period he signed an agreement with Louis of Taranto to cede him Capua , Aversa and other strongholds in the Kingdom of Naples . Werner subsequently fought for the lords of Forlì and Faenza against the papal legate , and , hired by Giacomo Pepoli of Bologna , helped him to return in his city , not before sacking it . After Bologna was sold back to the Visconti , Werner besieged it , but was defeated by Galeazzo II Visconti ' s army . In 1351 his company was unable to find any contract , until he was hired by Mastino II della Scala and then by the Visconti . Later , he returned to Swabia , where he died in 1354 . After his death , the leadership of the Grand Company went to Fra ' Moriale . He is said to have worn a breastplate with the inscription , " The enemy of God , of pity and of mercy . "