A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
From a drawing in 'Cassell's Library of English Literature', Henry Morley, 1883.
Source Firkin
This one needs to be used in small areas; you can see it repeat.
Source Luca
This one has rusty dark brown texture.
Source V. Hartikainen
This could be a hippy vintage wallpaper.
Source Tileable Patterns
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
It’s like Shine Dotted’s sister, only rotated 45 degrees.
Source mediumidee
ZeroCC tileable beechwood wood texture, generated in Neo Texture Edit by me. CC0
Source Sojan Janso
Here's a bluish gray striped background pattern for use on web sites.
Source V. Hartikainen
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Remixed from a raster on Pixabay that was uploaded by ArtsyBee.
Source Firkin
Three shades of gray makes this pattern look like a small carbon fiber surface. Great readability even for small fonts.
Source Atle Mo
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin