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
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
Derived from a PNG that was uploaded to Pixabay by nutkitten
Source Firkin
A brown seamless wood texture in a form of stripe pattern. The result has turned out pretty well, in my opinion.
Source V. Hartikainen
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
This is a hot one. Small, sharp and unique.
Source GraphicsWall
Super detailed 16×16 tile that forms a beautiful pattern of straws.
Source Pavel
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Lovely pattern with some good-looking non-random noise lines.
Source Zucx
Super dark, crisp and detailed. And a Kill Bill reference.
Source Badhon Ebrahim
Prismatic Geometric Pattern Background
Source GDJ
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
Not so subtle. These tileable wood patterns are very useful.
Source Elemis
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The tile can be had by using shift+alt+i on the selected rectangle in Inkscape
Source Firkin
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Have you wondered about how it feels to be buried alive? Here is the pattern for it.
Source Hendrik Lammers
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A free seamless background texture that looks like a brown stone wall.
Source V. Hartikainen