This could be a hippy vintage wallpaper.
Source Tileable Patterns
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A dark one with geometric shapes and dotted lines.
Source Mohawk Studios
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
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
This one needs to be used in small areas; you can see it repeat.
Source Luca
This is lovely, just the right amount of subtle noise, lines and textures.
Source Richard Tabor
Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
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
One can never have too few rice paper patterns, so here is one more.
Source Atle Mo
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Dark wooden pattern, given the subtle treatment. based on texture from Cloaks.
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Seamless pattern inspired by a drawing on Pixabay. To get the tile this is formed from, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Prismatic Abstract Geometric Background 4
Source GDJ
A seamless pattern with green and yellow diagonal lines on top of a white dotted background.
Source V. Hartikainen