Bohemian Lion

The original coat of arms of the Bohemian prince, and later king from the Přemyslid dynasty, was a black eagle, traditionally dating back to Prince and later patron saint of the land, Saint Wenceslas. Due to the added red flames, it is also referred to as the "flaming eagle."
Přemyslid eagle. Passional of Abbess Kunigunde, c. 1321. Wikimedia Commons
The Bohemian lion is said to have first become the coat of arms of a ruling Přemyslid during the reign of Vladislaus II, along with the royal title as a reward given by Emperor Frederick Barbarossa for military assistance in the conquest of Milan in 1158. At that time, it was still a lion with a single tail. The second tail was supposedly added to the lion as an enhancement of the coat of arms during the reign of Ottokar I as a reward for helping Roman King Otto IV to suppress a rebellion in Saxony. Both accounts come from the chronicler known as Dalimil and are considered more mythical than factual because of the lack of other evidence. The only real evidence from this period is the seal of Vladislaus Henry, Margrave of Moravia, from the early 13th century, depicting the Bohemian lion on a shield of a mounted figure. The use of the so-called Bohemian lion with two tails is reliably documented only from the period just before the mid-13th century, likely related to Ottokar II's accession as co-ruler (i.e., young king) with his father Wenceslas I. Thus, in the first half of the 13th century, Bohemian kings likely used both the original Přemyslid eagle and the Bohemian lion concurrently.
Bohemian Lion. Fresco in the Gozzo Palace (Gozzoburg) in Krems, 3rd quarter of the 13th Century. Wikimedia Commons
After Ottokar II's definitive accession to the throne, the two-tailed crowned silver lion became the dominant coat of arms of Bohemian kings, and Saint Wenceslas's Přemyslid eagle receded into the background. The oldest known color depiction of the Bohemian lion is a fresco in the Gozzo Palace (Gozzoburg) in Krems, Austria. The fresco dates to somewhere between 1250-1276, a period when Ottokar II had influence over and briefly ruled the Austrian territories. Later, in 1339, after the extinction of the main branch of the Přemyslid dynasty, King John of Luxembourg granted the eagle as a coat of arms to the Bishop of Trent. Thus, the Bohemian lion remained the primary coat of arms of the Bohemian kingdom, enduring with minor changes up to the present day as the "Lesser coat of arms of Czech Republic" and as part of the "Greater coat of arms of Czech Republic."
Bohemian Lion. Passional of Abbess Kunigunde, c. 1321. Wikimedia Commons
There have been lengthy discussions and various jokes about tha fact why the Bohemian lion has two tails. The most plausible theory suggests that the addition of the second tail occurred during Ottokar II's appointment as co-ruler during the lifetime of his father, Wenceslas I, symbolizing the shared rule with the still-living king.
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