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
To get the repeating unit, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Zero CC tileable brick texture, photographed and made by me. CC0
Source Sojan Janso
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Zero CC tileable Laminate wood texture, photographed and made by me. CC0
Source Sojan Janso
A seamless pattern created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
Derived from an image that was uploaded to Pixabay by TheDigitalArtist
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
Zero CC bark from fur tree tileable texture, photographed and made by me. CC0
Source Sojan Janso
Similar to original, but without gaps in between the arrows. This seamless pattern was created from a rectangular tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
This one is so simple, yet so good. And you know it. Has to be in the collection.
Source Gluszczenko
Classy golf-pants pattern, or crossed stripes if you will.
Source Will Monson
Remixed from a drawing in 'A Child of the Age', Francis Adams, 1894.
Source Firkin
A seamless pattern drawn originally in Paint.net by distorting a slice of background pattern 116 and copying the resulting triangle numerous times.
Source Firkin
A pattern derived from repeating unit cells each derived from part of a mosaic in paint.net. The starting point for the mosaic was a picture of some prawns!
Source Firkin
Prismatic Abstract Background Design
Source GDJ
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Retro Circles Background 5 No Black
Source GDJ
Actually, there's no clouds in it, but I think it looks quite nice.
Source V. Hartikainen
A seamless pattern drawn originally in Paint.net by distorting a slice of background pattern 116 and copying the resulting triangle numerous times.
Source Firkin
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin
Background Wall, Art Abstract, white Well & CC0 texture.
Source Ractapopulous