Our star catalog comes from the European Space Agency's Hipparcos mission, a high precision catalog of stars generated from over three year's of observations by the Hipparcos space-based telescope. You can read more about it here: https://www.cosmos.esa.int/web/hipparcos/home
We use this star catalog to render the positions of the stars for any date or location in the past or future!
You can compare the map you create here with any open source planetarium software before you order. We recommend Stellarium.org
Astronomers have carefully studied and measured the positions of the stars and the year-long orbit of the earth around the sun and so, using math and (yay!) science, it is possible to compute what stars will be above anywhere on the earth at any time! We use a catalog of star locations from the Hipparcos satellite and these computations to generate our Star Map unique to your chosen location and time.
The maps render stars all the way down to magnitude six (visible stars, under dark skies). If you follow the links to the create/edit page, you can see the maps updating as you make adjustments.
We do call it "wall art", but I assure you they are extremely accurate.