Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
A hint of orange color, and some crossed and embossed lines.
Source Adam Anlauf
A free background image with a seamless texture of cardboard. This texture of cardboard looks quite realistic, especially when is actually tiled.
Source V. Hartikainen
From a drawing of the coat of arms of the Ottoman Empire on Wikimedia.
Source Firkin
Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.
Source Firkin
A seamless texture of an abstract wall colored in shades of light orange brown.
Source V. Hartikainen
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Number 4 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Prismatic Abstract Geometric Background 4 No Black
Source GDJ
Classy golf-pants pattern, or crossed stripes if you will.
Source Will Monson
A free background pattern with abstract green tiles.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Prismatic Abstract Geometric Background derived from an image on Pixabay.
Source GDJ
Free tiled background with colorful stripes and white splatter.
Source V. Hartikainen
A playful triangle pattern with different shades of gray.
Source Dimitrie Hoekstra
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
Green Web Background, Seamless tile.
Source V. Hartikainen
Very simple, very blu(e). Subtle and nice.
Source Seb Jachec
Vector version of a JPG that was uploaded to Pixabay by theasad121
Source Firkin