Derived from a corner decoration itself found as a jpg on Pixabay.
Source Firkin
A beautiful dark padded pattern, like an old classic sofa.
Source Chris Baldie
Sort of reminds me of those old house wallpapers.
Source Tish
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Abstract Background Design
Source GDJ
Remixed from an image that was uploaded to Pixabay by CatherineClennan
Source Firkin
Colourful background achieved with gradient fills.
Source Firkin
Bigger is better, right? So here you have some large carbon fiber.
Source Factorio.us Collective
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
You know you can’t get enough of these linen-fabric-y patterns.
Source James Basoo
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
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin
Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen
From a drawing in 'Codogno e il suo territorio nella cronaca e nella storia'', Gio and Giarella Cairo, 1897.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Just like the black maze, only in light gray. Duh.
Source Peax
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
Colorful Floral Background No Black
Source GDJ