In the early days of the establishment of the Kingdom of Ithica, it was necessary to ensure the protection of the royalty. While during this time the Royalty, like the leaders of the surrounding kingdoms, warriors in their own right, battles were still wages with armies. The Royal Guard were elite members of the Ithican army, designed to protect, first and foremost, the persons of the royal family who were in line for to the throne, and to a lesser extent, the extended royal family.
They were created to be an elite protection force for the royal family. As the need for direction protection dwindled, the royal guard slowly morphed into a predominantly ceremonial role.
They were, because of this ceremonial role, often underestimated. Many a plot that relied on sneaking into places guarded by Royal Guards came undone by their specialist training.
As guards, they would be stationed at key strategic points throughout the the Citial, or the Spire. As such, they were masters at ensuring that only those authorised were in the area. They were trained in such arts forgery detection, the detection of lies and bluff, and were difficult to distract.
They were also masters as holding locations. Their training was in taking stock of the position they found themselves, and making it the most defensible they possible could. Their role to ensure that those whom they had charge to guard were able to escape whatever foe came at them.
They were also masters at remaining in one place, very still, for a very long time.