This is the reward for the SoD BETA. SoE is being very quiet about it, but here is a copy/paste from a forum. Supposed to be a copy/paste of a reply to a petition about it.
"Thank you for contacting Sony Online Entertainment, After reading your petition, I can inform you that the Mercenary Conscription Authorization is your Beta reward for participating in SoD beta. This grants you a flag that allows you to hire special mercenaries. Any details beyond this I am unable to disclose as this is brand new content. Thank you for your patience and understanding regarding this issue, If you have any further issues, feel free to contact us, and we will be glad to assist you."