The coat of arms of Spain represents Spain and the Spanish nation, including its national sovereignty and the country's form of government, a constitutional monarchy. It appears on the flag of Spain and it is used by the Government of Spain, the Cortes Generales, the Constitutional Court, the Supreme Court, and other state institutions. Its design consists of the arms of the medieval kingdoms that would unite to form Spain in the 15th century, the Royal Crown, the arms of the House of Bourbon, the Pillars of Hercules and the Spanish national motto: Plus Ultra. The monarch, the heir to the throne and some institutions like the Senate, the Council of State and the General Council of the Judiciary have their own variants of the coat of arms; thus the state coat of arms is not an arms of dominion.