Background Wall, Art Abstract, Star Well & CC0 texture.
Source Ractapopulous
I guess this is inspired by the city of Ravenna in Italy and its stone walls.
Source Sentel
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Not so subtle. These tileable wood patterns are very useful.
Source Elemis
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Very simple, very blu(e). Subtle and nice.
Source Seb Jachec
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
Might not be super subtle, but quite original in its form.
Source Alex Smith
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
A seamless pattern formed from miutopia's cakes on a tablecloth.
Source Firkin
Retro Circles Background 5 No Black
Source GDJ
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
No relation to the band, but damn it’s subtle!
Source Thomas Myrman
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
The following repeating website background is colored in a blue gray color and resembles a concrete wall or something similar to it.
Source V. Hartikainen
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin