Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
Bit of a strange name on this one, but still nice. Tiny gray square things.
Source Carlos Valdez
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
The original has been presented as black on transparent and stored in the pattern definitions. To retrieve the unit tile select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Prismatic Abstract Geometric Background 5
Source GDJ
More in the paper realm, this time with fibers.
Source Jorge Fuentes
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Abstract Tiled Background Extended 10
Source GDJ
A re-make of the Gradient Squares pattern.
Source Dimitar Karaytchev
Inspired by a 1930s wallpaper pattern I saw on TV.
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
A free seamless background image with a texture of dark red "canvas". It should look very nice on web sites.
Source V. Hartikainen
Thin lines, noise and texture creates this crisp dark denim pattern.
Source Marco Slooten
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Imagine you zoomed in 1000X on some fabric. But then it turned out to be a skeleton!
Source Angelica
This background has abstract texture with some similarities to wood.
Source V. Hartikainen
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
This is so subtle you need to bring your magnifier!
Source Carlos Valdez
The tile can be had by using shift+alt+i on the selected rectangle in Inkscape
Source Firkin