This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Free tiled background with colorful stripes and white splatter.
Source V. Hartikainen
The image is the remix of "wire-mesh fence seamless pattern" .This is a more minute version of it.Sorry for the file size.Using path>difference in Inkscape, I will cut out any silhouette from this pattern and create a "meshed silhouette".
Source Yamachem
A seamlessly tileable pink background texture.
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
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Fake or not, it’s quite luxurious.
Source Factorio.us Collective
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
A simple but elegant classic. Every collection needs one of these.
Source Christopher Burton
This is a grid, only it’s noisy. You know. Reminds you of those printed grids you draw on.
Source Vectorpile
A free seamless background with pink spots.
Source V. Hartikainen
Seamless Prismatic Geometric Pattern With Background
Source GDJ
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman
This is a remix of "blue wave-seigaiha".I hope this subtle color version of Seigaiha would be suitable for background .
Source Yamachem
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A black tile-able background with paper-like texture.
Source V. Hartikainen