This background has abstract texture with some similarities to wood.
Source V. Hartikainen
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
From a drawing in 'Royal Ramsgate', James Simson, 1897.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
Remixed from a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Greyscale version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
Prismatic Geometric Pattern Variation 2 With Background
Source GDJ
Just what the name says, paper fibers. Always good to have.
Source Heliodor jalba
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
A simple circle. That’s all it takes. This one is even transparent, for those who like that.
Source Saqib
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
An abstract Background pattern of purple twisty patterns.
Source TikiGiki
A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.
Source Firkin
This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin