I imagined how an assassin would look like if the Creed had a bureau in Wallachia in the 15th century(current Romania). I imagined him as a shepherd, a simple, honest and prideful man.
The cloak is made out of sheep hide and is called (șuba). It's the most defining clothing of a romanian shepherd.
When putting the hood on, he can easily pass as a sheep and avoid detection when being pursued or stalking targets within the safety of the herd.