It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
Tile available in Inkscape using shift-alt-i on the selected rectangle
Source Firkin
Prismatic Abstract Geometric Background 5 No Black
Source GDJ
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
Nothing like a clean set of bed sheets, huh?
Source Badhon Ebrahim
Prismatic Curved Diamond Pattern 6 No Background
Source GDJ
This reminds me of Game Cube. A nice light 3D cube pattern.
Source Sander Ottens
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
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A pale yellow background pattern with vertical stripes. The stripes are partially faded. I think this background image turned out pretty well, especially those faded stripes.
Source V. Hartikainen
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
This one is super crisp at 2X. Lined paper with some dust and scratches.
Source HQvectors
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Here's a new paper-like background for free use on personal and commercial projects (this applies to all background patterns here).
Source V. Hartikainen
More bright luxury. This is a bit larger than fancy deboss, and with a bit more noise.
Source Viszt Péter
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Prismatic Abstract Geometric Background 4 No Black
Source GDJ