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
Background Wall, Art Abstract, Blue Well & CC0 texture.
Source Ractapopulous
Hexagonal dark 3D pattern. What more can you ask for?
Source Norbert Levajsics
It’s big, it’s gradient—and it’s square.
Source Brankic1979
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Colorful Floral Background No Black
Source GDJ
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A free background image with a seamless texture of cardboard. This texture of cardboard looks quite realistic, especially when is actually tiled.
Source V. Hartikainen
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
A classic dark tile for a bit of vintage darkness.
Source Listvetra
From an image on opengameart.org shared by rubberduck.
Source Firkin
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry