The Arch was originally commissioned by King Ja'kreen in 598 DE, and was designed to be a replica of a similar arch on the D'ni's original home world of Garternay. Construction took place between 600 and 625 DE, overseen by Guild Master Koris. It was completed in 625 DE, the first year of the second century DE.
Ja'kreen felt strongly that the Arch should be built to enable the prophecy of the Great King to come to pass, and all subsequent kings—including the "Great King" Ahlsendar himself—sailed beneath it on the way to their coronation. According to legend, Ahlsendar was born beneath the Arch as his family escaped an attack on D'ni by the Pento. When he returned, he was hailed as the Great King.
On his deathbed, King Rikooth saw his son, Kerath, sailing through the Arch on a lizard shaped boat, returning from exile. According to legend he felt Yahvo moving him to declare Kerath the next king. The Arch of Kings would later be renamed the Arch of Kerath to honor the last King of D'ni.