A state banner was used in Poland as insignia of the head of state (king, president, etc.) as early as the 11th century CE. Although its design changed with time, it was always a heraldic banner, i.e. one based directly on the national coat of arms: a crowned White Eagle in a red field. In 1919, the Sejm (lower house of parliament) established the Banner of the Republic of Poland, reserved for use by the head of state – the State Leader ("Naczelnik Państwa") and, later, President of the Republic. In 1927, it was modified to reflect the adoption of a new official rendering of the national coat of arms. At this point the banner was virtually identical to the current design for the presidential jack.