The Bleach: Thousand-Year Blood War anime is greatly expanding the world and character roster for the entire franchise. Nearly all the Arrancar saga's villains are now either dead, lost, or captured, so protagonist Ichigo Kurosaki and his Soul Reaper friends need new enemies to fight. That enemy arrived in the form of the Wandenreich, the Quincy empire, led by the elite Sternritter. And there's a lot more of them than the Soul Reapers expected.
Source：https://www.cbr.com/bleach-four-elite-guards-explained/
