Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers
Remixed from a raster on Pixabay that was uploaded by ArtsyBee.
Source Firkin
ZeroCC tileable wood boards texture, photographed and made by me. CC0
Source Sojan Janso
Derived from a drawing in 'Elfrica. An historical romance of the twelfth century', Charlotte Boger, 1885
Source Firkin
This background has abstract texture with some similarities to wood.
Source V. Hartikainen
Looks like an old wall. I guess that’s it then?
Source Viahorizon
From a drawing in 'Picturesque New Guinea', J Lindt, 1887.
Source Firkin
Colour version of the original pattern inspired by the front cover of 'Old and New Paris', Henry Edwards, 1894.
Source Firkin
This one is amazing, truly original. Go use it!
Source Viahorizon
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
I skipped number 3, because it wasn’t all that great. Sorry.
Source Dima Shiper
Prismatic Abstract Background Design No Black
Source GDJ
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
Nothing like a clean set of bed sheets, huh?
Source Badhon Ebrahim
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Abstract Ellipses Background Grayscale
Source GDJ
Black brick wall pattern. Brick your site up!
Source Alex Parker
More in the paper realm, this time with fibers.
Source Jorge Fuentes
It’s like Shine Dotted’s sister, only rotated 45 degrees.
Source mediumidee
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Not the Rebel alliance, but a dark textured pattern.
Source Hendrik Lammers
Light gray version of the Binding pattern that looks a bit like fabric.
Source Newbury
From a drawing in 'Hundert Jahre in Wort und Bild', S. Stefan, 1899.
Source Firkin