When Conan joined Free Companions they were led by Amalric the Lion and they were in employ of King of Koth - Strabonus fighting against Corinthia. When Strabonus stopped paying Amalric had kothian magistrate hanged and the city they were in sacked. After that he decided to lead them south. Five days later they encountered remnants of Khorajan army that was ambushed by Ophir. Count Thespides led them back to Khoraja where Princess Yasmela asked Amalric for help and later influenced by Mitra's prophecy gave Conan combined command of her armies (Amalric retained command of mercenary legion). Conan led her armies to face rebel forces of Natohk the Veiled One to Shemla Pass where thanks to Amalric's advice and wise strategy they defeated more numerous army. Unfortunately Amalric was wounded and later died of infection, before his death he gave command of Free Companions to Conan.
For some time they stayed in Khoraja, helping free King Khossus and taking part in bloodless battle with Kothian army. Eventually princess Yasmela gave command of Khorajan forces to Julion and he dismissed Free Companions from Khoraja's employ.
For some time they were ravaging Koth and Corinthian territories slowly making their way east towards Turan. There they plundered south-west shores of Vilayet Sea until Shah Amhurat decided to put a stop to this. He ambushed Conan's legion only to suffer a crushing defeat. Shah returned to Akif where he met with Sergius - leader of Red Brotherhood who revealed to him place where Free Companions camped. This time he surprised Conan completely and in the bloody battle at the Ilbars River destroyed Free Companions - 5000 man perished in Vilayet's marshes. Conan luckily survived massacre but that was the end of his mercenary army. ... or was it? They said that Free Companions exist until last of them dies.