Today the suits would likely be worth millions of dollars, though the value is difficult to estimate because none of the royal armor been sold since the 19th century.

"They were the most favorite objects of any king, any prince in Europe because they were his own suit," del Campo said, noting that anyone who visited the king would likely first tour the Royal Armory. "If in the 16th century, you have armor decorated in this way, it means you belong to the most powerful family of Europe."

A common symbol linking many of the pieces on view is the Golden Fleece on the collar, a small medallion that depicts a sheepskin, which is a symbol the chivalric order. Even today, the king of Spain wears the Golden Fleece at official events because he is the master of the order.

The exhibit also features armor worn by young boys in the royal family. One piece was commissioned by Philip II for his son, Philip III.

"This armor talks about the cardinal virtues — strength, temperance, justice — they are depicted here," del Campo said, describing the piece, which includes a depiction of Minerva, the Roman goddess of wisdom and war. "What they are trying to say with this decoration is how should be the life of the prince."

In many ways, a piece of armor could be a portrait in itself — custom made for the monarch to tell of his character and accomplishments.

Many pieces take inspiration from the Bible or mythology.

Emperor Maximilian I's equestrian parade armor, for example, features scenes across the front of the horse's breastplate from the biblical story of Samson, along with Hercules of classical mythology. The message for the person riding the horse, then, is, "The Force Be with You," del Campo said — just like the running theme in the "Star Wars" movies.

"So," he said, "George Lucas, I think, was into the armory."