The tile for this is based on a repeating unit close to a design on Pixabay. It can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Prismatic Abstract Geometric Background 2
Source GDJ
This is a grid, only it’s noisy. You know. Reminds you of those printed grids you draw on.
Source Vectorpile
Geometric triangles seem to be quite hot these days.
Source Pixeden
Inspired by a 1930s wallpaper pattern I saw on TV.
Source Firkin
A light gray wall or floor (you decide) of concrete.
Source Atle Mo
Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida
Pattern formed from simple shapes. Black version.
Source Firkin
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
Zero CC tileable ground (#2) cracked, crackled texture, made by me. CC0
Source Sojan Janso
Zero CC bark from fur tree tileable texture, photographed and made by me. CC0
Source Sojan Janso
Prismatic Snowflakes Pattern No Background
Source GDJ
Prismatic Curved Diamond Pattern 7 No Background
Source GDJ
A repeating background with dark brown stone-like texture and abstract pattern that looks like tree trunks.
Source V. Hartikainen
Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev