Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.
Source Simon Meek
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Prismatic Groovy Concentric Background No Black
Source GDJ
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
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
Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
Derived from an image that was uploaded to Pixabay by darkmoon1968
Source Firkin
Wild Oliva or Oliva Wilde? Darker than the others, sort of a medium dark pattern.
Source Badhon Ebrahim
Heavily remixed from a drawing that was uploaded to Pixabay by ractapopulous
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
A beautiful dark wood pattern, superbly tiled.
Source Omar Alvarado
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
A white version of the very popular linen pattern.
Source Ant Ekşiler
Used in small doses, this could be a nice subtle pattern. Used on a large surface, it’s dirty!
Source Paul Reulat
A repeating gloomy background image. This one consists of a pattern of black chains layered on top of a dark textured background.
Source V. Hartikainen
Subtle scratches on a light gray background.
Source Andrey Ovcharov
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
A free seamless background with pink spots.
Source V. Hartikainen
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin