The Azran Civilization is an ancient civilization that existed millions of years before the events of the Professor Layton Series. The knowledge of their existence in the games didn't come to light until Professor Layton and the Miracle Mask, however it was hinted at in Professor Layton and the Last Specter and Professor Layton and the Eternal Diva.
This civilization was heavily researched by Donald Rutledge, who theorized that the Azrans had a language and technology much more advanced than their own. This theory can be proved through the three legacies they left behind; the Golden Garden, Ambrosia, and the Nautilus Chamber of Akbadain. The devious group known as Targent are out to unlock these secrets of the legacies, in order to gain the power of the Azrans. Although the civilization was wiped out, Aurora was the only remaining Azranian alive, and had been encased in ice for a million years until she was discovered in Professor Layton and the Azran Legacy by Desmond Sycamore.
Millions of years before the events in the games, the Azran Civilization existed as the greatest civilization to ever rise and fall. They were masters in science and technology, and were rather arrogant, leading them to believe they were gods. They built golems to serve as their slaves, and programmed them to even have emotions. Eventually, the golems pleaded for freedom, but the Azrans refused it, and so they rebelled, wiping out the entire civilization that had created them. After being wiped out, the Azrans left behind three legacies; the Golden Garden in Misthallery, the City of Harmony Ambrosia, and the Nautilus Chamber of Akbadain near Monte d'Or. Aurora, who was another golem created by the Azrans, was encased in ice for a million years to act as the guardian for the Azran's sanctuary, as well as the Azran emissary.
Five aura stones were also scattered around the world, which when combined, served as the key to unlocking the power of the Azran, which would turn out to be the release of the Azran golems to allow the human race to suffer the same fate as the Azrans.