From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
A seamless pattern the starting point for which was a 'light rays' rendering in Paint.net.
Source Firkin
Inspired by a pattern seen on a public domain image of a very old tile. To get the unit cell, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
The image depicts a seamless pattern of a snow crystal.I referred to a book called ”sekka-zusetsu” or "雪華図説" which means an illustrated explanation about snow crystals.This book was published in 1832 (天保3年) or Edo period.For more about "雪華図説",see here:dl.ndl.go.jp/info:ndljp/pid/2536975
Source Yamachem
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
This seamless light brown background texture resembles a wallpaper with vertical stripes. One way to use it is as a tiled background on web sites.
Source V. Hartikainen
A hint of orange color, and some crossed and embossed lines.
Source Adam Anlauf
A new take on the black linen pattern. Softer this time.
Source Atle Mo
Prismatic Abstract Geometric Background 3
Source GDJ
This makes me wanna shoot some pool! Sweet green pool table pattern.
Source Caveman
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
This ons is quite old school looking. Retro, even. I like it.
Source Arno Declercq
Submitted by DomainsInfo – wtf, right? But hey, a free pattern.
Source DomainsInfo
One more updated pattern. Not really carbon fiber, but it’s the most popular pattern, so I’ll give you an extra choice.
Source Atle Mo
Zero CC tileable bark texture, photographed and made by me. CC0
Source Sojan Janso
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
Remixed from a PNG that was uploaded to Pixabay by gingertea
Source Firkin
Bright Multicolored Floral Background by Karen Arnold from PDP.
Source GDJ
A seamless textured paper for backgrounds. Colored in pale orange hues.
Source V. Hartikainen
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ