Complex sentence: Most Spanish noble titles are granted as "títulos del Reino" ("Peer of the Realm "), many of which predate the modern Spanish monarchy, so the Kings of Spain adopted the ancient dignity of"Grande" as an additional rank of honour.
Split into simpler sentences: Most Spanish noble titles are granted as "títulos del Reino" ("Peer of the realm "), many of which predate the modern Spanish monarchy. The Kings of Spain re-established the ancient dignity of"Grande" to confer as an additional rank of honour.