A seamless background texture of old cardboard.
Source V. Hartikainen
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Prismatic Geometric Pattern Background No Black
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
"Beige Stone", Tileable Texture.
Source V. Hartikainen
From a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
A green background pattern with warped vertical stripes and a grunge look.
Source V. Hartikainen
Number 4 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
Remixed from a drawing in 'Jezebel's Daughter', Wilkie Collins 1880
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
Black And White Floral Pattern Background Inverse
Source GDJ
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
Here's a bluish gray striped background pattern for use on web sites.
Source V. Hartikainen
Bright Multicolored Floral Background by Karen Arnold from PDP.
Source GDJ
A dark brown fabric-like background texture with seamless pattern of winding stripes.
Source V. Hartikainen
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective