Due to dissonance in the time-space corridor between Earth and Seifall, all the Transferees come from approximately the same time frame on Earth; the Gods simply pull them out in different points in the Seifall timeline.
When Ryouma has his first meeting with Gain, Lulutia and Kufo, he asks if he will meet any other Transferees. They tell him that they only need to pull mana (accompanied by a soul to be re-incarnated) from Earth every 150-200 years or so, so it's not likely. However, according to the scraps of information we have about the Transferees, almost all of them must have come from the late nineteenth century at the very earliest, but far more likely the twentieth or even twenty-first. Ryouma himself is definitely from the twenty-first (this is made clear in the 'those left behind' side chapters in the LN's).- The founder of Taming Magic, future Duchess of House Jamil: when the Gods mention her in the anime, she's shown wearing a seifuku (a Japanese school uniform modeled on a sailor's uniform). These started to be worn in the late nineteenth century, but didn't become really widespread until the twentieth.
- LN vol 8 reveals that her first name was Shiho, and she gave the fairy who was her familiar the name Yui; which would seem to confirm that she was Japanese at least.
- The other Transferee that Eliaria is descended from, the master fire magician: Kufo refers to him as an 'otaku', a term that didn't come into use until 1983. If he was speaking metaphorically, the kinds of hobbies that would make someone fit the term note didn't really come into being until the twentieth century.
- The Transferee who 'created' the airport (Miyabi's ancestor): the first commercial airport was founded in approximately 1911 (some sources disagree as to which it was). The first passenger plane was made in 1933.
- The Alchemy King: the Gods created alchemy magic at his demand. While alchemy has been around in some form or another since at least the middle ages, the kind of alchemy in the series needs a solid history of chemistry to work well, especially in the kind of detail Ryouma and the King used. While the science of chemistry has been around for quite some time, it being common knowledge (rather than something only the rich could study) is definitely a late nineteenth/twentieth century thing.
- When Ryouma undergoes testing at the Adventurer's Guild in Gimel, his archery is tested by a clay target launcher, which was apparently invented by an adventurer to use with his unique skill (or possibly weapon) 'shotgun': the first recorded use of the term shotgun was in 1776, and clay targets began to be used in around 1875. Launchers like the one shown in the anime, however, were developed sometime later.
- The Transferee worshiped as a Saint of Healing: at one point, a transferee who had near-miraculous healing powers is mentioned, including that her dying wish healed just about everyone on the planet who was sick at the time. This is the one Transferee who can't be pinpointed in this time frame. However, her wish for healing powers implies that a great many sick people were on her mind. She could have been a doctor or nurse, but a lot of sick people at once? An epidemic comes to mind - like the Spanish Flu epidemic of 1918, perhaps?
