Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A re-make of the Gradient Squares pattern.
Source Dimitar Karaytchev
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin
Alternative colour scheme for the original floral pattern.
Source Firkin
Prismatic 3D Isometric Tessellation Pattern 6
Source GDJ
From a drawing in 'Handbook of the excursions proposed to be made by the Lincoln Diocesan Architectural Society, on the 27th and 28th of May, 1857', Edward Trollope, 1857.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
This one looks like a cork panel. Feel free to use it as a tiled background on your blog or website.
Source V. Hartikainen
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
Prismatic Abstract Line Art Pattern Background
Source GDJ
Remixed from a drawing in 'Prehistoric Man: researches into the origin of civilisation in the old and the new world', Daniel Wilson, 1876.
Source Firkin
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne
Zero CC tileable ground (#2) cracked, crackled texture, made by me. CC0
Source Sojan Janso
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Pass parameters to the URL or edit the source code variables to configure the graph paper for the division desired.
Source JayNick
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
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
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin