A repeating background of thick textured paper. Actually, it turned out to look like something between a paper and fabric.
Source V. Hartikainen
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'A Rolling Stone. A tale of wrongs and revenge', John Hartley, 1878.
Source Firkin
One more sharp little tile for you. Subtle circles this time.
Source Blunia
A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.
Source Atle Mo
This one needs to be used in small areas; you can see it repeat.
Source Luca
The image is a design of blue glass.How about using it as background image?
Source Yamachem
Prismatic Geometric Pattern Background 2
Source GDJ
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
A seamless web texture with illustration of pale color stains on canvas.
Source V. Hartikainen
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic 3D Isometric Tessellation Pattern 6
Source GDJ
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
Like the name says, light and gray, with some small dots and circles.
Source Brenda Lay
Colour version that is close to the original drawing uploaded to Pixabay by pencilparker.
Source Firkin
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee
A fun-looking elastoplast/band-aid pattern. A hint of orange tone in this one.
Source Josh Green
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From an image on opengameart.org shared by rubberduck.
Source Firkin
This one could be the shirt of a golf player. Angled lines in different thicknesses.
Source Olivier Pineda
A seamless gray background texture suitable for use on websites. To me, it has the look of stone. Feel free to modify it to meet your needs (by making it a bit lighter or darker, for example).
Source V. Hartikainen