Flags of the Holy Roman Empire

The flag of the Holy Roman Empire was not a national flag, but rather an imperial banner used by the Holy Roman Emperor; black and gold were used as the colours of the imperial banner, a black eagle on a golden background. After the late 13th or early 14th century, the claws and beak of the eagle were coloured red.

Source: Wikipedia — Flags of the Holy Roman Empire (CC BY-SA 4.0)