Heraldry of León
The lion is the heraldic symbol of the Spanish city of León and its province. It was also the symbol of the Kingdom of León before the kingdom of Spain existed. It was used for the first time in the coins minted by King Alfonso VII (1126–1157). Before that, the symbol mainly used by the Leonese kings in documents and on their coins was the cross. Since Alfonso VII's reign, the cross became more and more often replaced by the lion.
The first written reference of the lion as a symbol of the King and, therefore, of the kingdom, is in the Chronica Adefonsi Imperatoris. This was written during the reign of Alfonso VII. The lion is one of the oldest symbols used in heraldry in Europe that still exist. It is earlier than the castle, which was used by the neigbouring Kingdom of Castile.
The flag of León is red, with the coat of arms of in the middle.
Heraldry Of León Media
The Royal Standard of León preceding to the Council of the City, at the procession to Royal Collegiate of San Isidoro of the "Forum or Offer" Ceremony
Modern reconstruction of a flag used during the reign of Alfonso VII (1105-1157)
Flag of the city of León
The purpurada, a flag used by regionalists to represent León (Unofficial)
Flag used by some leftist groups to represent the region of León (Unofficial)