The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Prismatic Abstract Geometric Background 4 No Black
Source GDJ
Number five from the same submitter, makes my job easy.
Source Dima Shiper
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
A seamless marble-like texture colored in light blue.
Source V. Hartikainen
Medium gray fabric pattern with 45-degree lines going across.
Source Atle Mo
A classic dark tile for a bit of vintage darkness.
Source Listvetra
Prismatic Groovy Concentric Background 3
Source GDJ
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.
Source Atle Mo
Colour version of the original pattern.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Prismatic Curved Diamond Pattern No Background
Source GDJ
Fake or not, it’s quite luxurious.
Source Factorio.us Collective
One more in the line of patterns inspired by Japanese/Asian styles. Smooth.
Source Kim Ruddock
Derived from an image that was uploaded to Pixabay by darkmoon1968
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Derived from a JPG that was uploaded to Pixabay by ractapopulous
Source Firkin
Smooth Polaroid pattern with a light blue tint.
Source Daniel Beaton
Here's a camo print with more tan and less green, such as might be used in a desert scenario. This is tileable, so it can be used as a wallpaper or background.
Source Eady
Prismatic Rounded Squares Grid 4 No Background
Source GDJ