A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A free seamless background with pink spots.
Source V. Hartikainen
Seamless tile drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
A large (588x375px) sand-colored pattern for your ever-growing collection. Shrink at will.
Source Alex Tapein
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
The image a seamless pattern derived from a weed which I can't identify.The original weed image is from here:https://jp.pinterest.com/pin/500744052301423641/
Source Yamachem
Background Wall, Art Abstract, Star Well & CC0 texture.
Source Ractapopulous
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
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
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857
Source Firkin
There are quite a few grid patterns, but this one is a super tiny grid with some dust for good measure.
Source Dominik Kiss
I’m not going to use the word Retina for all the new patterns, but it just felt right for this one. Huge wood pattern for ya’ll.
Source Atle Mo
Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
The original enhanced with one of Inkscapes's filters.
Source Firkin
Prismatic Snowflakes Pattern 3 No Background
Source GDJ
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
Zero CC tileable hard cover red book, scanned and made by me. CC0
Source Sojan Janso
Seamless pattern formed from a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin