Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
Sometimes you just need the simplest thing.
Source Fabricio
Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Embossed lines and squares with subtle highlights.
Source Alex Parker
From a drawing in 'Bond Slaves. The story of a struggle.', Isabella Varley, 1893.
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
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
A seamless pattern of leopard skin. It should look nice as a background element on web pages.
Source V. Hartikainen
The image depicts a seamless pattern of pine tree leaves.
Source Yamachem
Floral patterns will never go out of style, so enjoy this one.
Source Lasma
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Did anyone say The Hoff? This pattern is in no way related to Baywatch.
Source Josh Green
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Sounds like something from World of Warcraft. Has to be good.
Source Tony Kinard