Wikipedia
Martolos
The martolos was an internal security force of the Ottoman Empire in the Balkans ( Rumelia), mostly active between the 15th to 17th centuries. It initially constituted out of the local mostly Christian populations ( Rum Millet), but over time members converted into Islam. For their military service, they were given privileged status (as askeri), in relation to the Rayah. Their commanders were predominantly Muslim.