World of Broken Blade?

[Mafty]

So how much information is there on the setting of the Broken Blade series?

Spoiler

The continent of Cruzon heavily resembles a desert version of Japan (at least in the maps shown in the Anime)

So is the setting ever explained?

Spoiler

Is Cruzon future Japan? or is it an alternate world with a similear land mass (like how in Argevollen the continent resembles South East Asia with continental European and Japanese architecture depending on the city/country.

[Seto Kaiba]

So how much information is there on the setting of the Broken Blade series?

Little to nothing outside the story itself.

So is the setting ever explained?

The "present day" of the setting is well explained in-story, but anything to do with the ancient civilization is left as a mystery to the reader and cast alike. There is not enough information to know if it's meant to be a far future story, an alternate world story, etc.

Spoiler

All we can say with confidence is that the Ancients were a technologically advanced civilization of unsorcerers (given that the Delphine is technological not magical and that it identifies sorcerer Humans as an "unidentified organism") and that they probably spoke English and Japanese (since those are the languages the Delphine's UI uses).

Whether any proper explanation was ever planned is unknown, since the series was cancelled due to the author's failing health and its declining sales, so no explanation has been forthcoming. It doesn't actually matter much to the story, so it probably wasn't a priority.

(In a way, it's reminiscent of the backstory situation in Five Star Stories. Humanity in FSS doesn't even know what planet it evolved on because records from the pre-Joker era were lost when the ancient Super Empire collapsed and the advanced technology and magic they use are degenerate copies of that long-vanished ancient civilzation's abilities. Like the Ancients in Break Blade, the fate of the Farus Di Kanon Empire in FSS is an interesting mystery in-story but ultimately irrelevant to the story proper.)