This is the third pattern called Dark Denim, but hey, we all love them!
Source Brandon Jacoby
A dark metal plate with an embossed grid pattern and a bit of rust. Here's a dark metal plate texture for use as a tiled background on web pages.
Source V. Hartikainen
A seamless web texture with illustration of pale color stains on canvas.
Source V. Hartikainen
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Found on the ground in french cafe in kunming, Yunnan, china
Source Rejon
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
Continuing the geometric trend, here is one more.
Source Mike Warner
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
The classic notebook paper with horizontal stripes.
Source Are Sundnes
Lovely light gray floral motif with some subtle shades.
Source GraphicsWall
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
Prismatic Abstract Geometric Background 4
Source GDJ
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight