A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
A light gray background pattern with seamless fabric-like texture and almost unnoticeable stripes.
Source V. Hartikainen
Might not be super subtle, but quite original in its form.
Source Alex Smith
A free seamless background image with abstract texture of green "curtain".
Source V. Hartikainen
Number 3 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
From a drawing in 'Az Osztrák-Magyar Monarchia irásban és képben', 1885.
Source Firkin
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Derived from a corner decoration itself found as a jpg on Pixabay.
Source Firkin
This one could be the shirt of a golf player. Angled lines in different thicknesses.
Source Olivier Pineda
Prismatic Geometric Tessellation Pattern 3 No Background
Source GDJ
Your eyes can trip a bit from looking at this – use it wisely.
Source Michal Chovanec
Alternative colour scheme for the original floral pattern.
Source Firkin
A seamless pale yellow paper background with a pattern of animal tracks.
Source V. Hartikainen
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
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin