Spanish heraldry

The tradition and art of heraldry first appeared in Spain at about the beginning of the eleventh century AD and its origin was similar to other European countries: the need for knights and nobles to distinguish themselves from one another on the battlefield, in jousts and in tournaments. Knights wore armor from head to toe and were often in leadership positions, so it was essential to be able to identify them on the battlefield.

The design of the arms themselves, excepting for the rules of heraldry, were up to the owner, and sometimes the design had a specific meaning or symbolism. Originally, anyone could bear (display) arms. Later, it became more of a practice for the nobility. Until the end of the middle ages only the paternal arms were used but later both the paternal and maternal arms were displayed. The arms of the maternal and paternal grandfathers were impaled (shield cut in half vertically, showing the respective arms on each half). During the 18th and 19th centuries, the use of four quarterings came into use by the nobility (the shield was cut into four parts and the design of the arms of each grandparent was placed in each quarter). The order of display was:

The Spanish nobility, unlike their other European counterparts, was based almost entirely on military service. Few families of eminence came from the law, commerce or the church. The great families of Spain and Portugal fought their way to their rank, which allowed commoners to join the ranks of the nobility through loyal and successful military service. Many poor families came to prominence and wealth quickly as a result of their successful military exploits. In Spanish heraldry, arms are a symbol of lineage and a symbol of the family as well. Spanish arms are inheritable like any other form of property.

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Wikipedia