A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless green background texture. The image is distributed under a Creative Commons License (like all of the images here).
Source V. Hartikainen
Snap! It’s a pattern, and it’s not grayscale! Of course you can always change the color in Photoshop.
Source Atle Mo
The tile can be had by using shift+alt+i on the selected rectangle in Inkscape
Source Firkin
Same classic 45-degree pattern, dark version.
Source Luke McDonald
Feel free to download and use it, or see the rest of the dark background patterns that I have made. Anyway, I hope you will find something that you like.
Source V. Hartikainen
Coming in at 666x666px, this is an evil big pattern, but nice and soft at the same time.
Source Atle Mo
You know I love paper patterns. Here is one from Stephen. Say thank you!
Source Stephen Gilbert
Wild Oliva or Oliva Wilde? Darker than the others, sort of a medium dark pattern.
Source Badhon Ebrahim
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
Remixed from a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
A free background pattern with abstract green tiles.
Source V. Hartikainen
Very simple, very blu(e). Subtle and nice.
Source Seb Jachec
Background Wall, Art Abstract, Watercolor Vintage style CC0 texture.
Source Ractapopulous
A version without colours blended together to give a different look.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
From a drawing in 'Az Osztrák-Magyar Monarchia irásban és képben', 1885.
Source Firkin
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin