From a drawing in 'Handbook of the excursions proposed to be made by the Lincoln Diocesan Architectural Society, on the 27th and 28th of May, 1857', Edward Trollope, 1857.
Source Firkin
A good starting point for a cardboard pattern. This would work well in a variety of colors.
Source Atle Mo
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
I asked Gjermund if he could make a pattern for us – result!
Source Gjermund Gustavsen
Prismatic Abstract Background Design No Black
Source GDJ
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
Basket Fibers, Basket Texture, Braid Background style CC0 texture.
Source 1A-Photoshop
A repeating background with seamless texture of stone. There haven't been any stone-like backgrounds for a while, so I have decided to create one more. The rest can be found in the appropriate category.
Source V. Hartikainen
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
I scanned a paper coffee cup. You know, in case you need it.
Source Atle Mo
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
The basic shapes never get old. Simple triangle pattern.
Source Atle Mo
Black brick wall pattern. Brick your site up!
Source Alex Parker
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
You were craving more leather, so I whipped this up by scanning a leather jacket.
Source Atle Mo
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Derived from an image that was uploaded to Pixabay by TheDigitalArtist
Source Firkin
The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
Kaleidoscope Prismatic Abstract No Background
Source GDJ