The image depicts an edo-era pattern called "same-komon" or "鮫小紋"which looks like a shark skin.The "same" in Japanese means shark in English.
Source Yamachem
This ladies and gentlemen, is texturetastic! Love it.
Source Adam Pickering
Prismatic Geometric Pattern Background No Black
Source GDJ
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Sweet and subtle white plaster with hints of noise and grunge.
Source Phil Maurer
This background has abstract texture with some similarities to wood.
Source V. Hartikainen
Sounds French. Some 3D square diagonals, that’s all you need to know.
Source Graphiste
Square design drawn in Paint.net and vectorized in Vector Magic.
Source Firkin
ZeroCC tileable stone texture, edited from pixabay. CC0
Source Sojan Janso
Vector version of a JPG that was uploaded to Pixabay by theasad121
Source Firkin
This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
Stefan is hard at work, this time with a funky pattern of squares.
Source Stefan Aleksić
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski
Derived from an image that was uploaded to Pixabay by TheDigitalArtist
Source Firkin
Remixed from a PNG that was uploaded to Pixabay by gingertea
Source Firkin
Here's a seamless brown cork board background texture. Feel free to download or reshare if you like.
Source V. Hartikainen
Awesome name, great pattern. Who does not love space?
Source Nick Batchelor
This one is amazing, truly original. Go use it!
Source Viahorizon
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
Abstract Tiled Background Extended 10
Source GDJ
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin