Dailamite

The Daylamites or Dailamites (Middle Persian: Daylamig; Persian: دیلمیان‎‎ Deylamiān) were an Iranian people inhabiting the mountainous regions of northern Iran on the southern shore of the Caspian Sea. They were employed as soldiers from the time of the Sasanian Empire, and long resisted the Muslim conquest of Persia and subsequent Islamization. In the 930s, the Daylamite Buyid dynasty emerged and managed to gain control over much of modern-day Iran, which it held until the coming of the Seljuq Turks in the mid-11th century.

The Daylamites lived in the highlands of Daylam, part of the Alborz range, between Gilan and Tabaristan. However, the earliest Zoroastrian and Christian sources indicate that the Daylamites originally came from Anatolia near the Tigris, where Iranian ethnolinguistic groups, including Zazas, live today. They spoke the Daylami language, a now-extinct northwestern Iranian variety similar to that of the neighbouring Gilites. During the Sasanian Empire, they were employed as high-quality infantry. According to the Byzantine historians Procopius and Agathias, they were a warlike people and skilled in close combat, being armed each with a sword, a shield and spears or javelins.

...
Wikipedia