From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
Zero CC tileable hard cover green book, scanned and made by me. CC0
Source Sojan Janso
This ladies and gentlemen, is texturetastic! Love it.
Source Adam Pickering
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
A mid-tone gray pattern with some cement looking texture.
Source Hendrik Lammers
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
Uses spirals from Pixabay. To get the basic tile select the rectangle in Inkscape and use shift+alt+i
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Prismatic Hexagonalism Pattern No Background
Source GDJ
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
The basic shapes never get old. Simple triangle pattern.
Source Atle Mo
Tile available in Inkscape using shift-alt-i on the selected rectangle
Source Firkin
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Here I have tried to create something that would look like maple wood. Not sure how well it's turned out, but at least it looks like wood.
Source V. Hartikainen
Dark wooden pattern, given the subtle treatment. based on texture from Cloaks.
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Polyskelion Pattern No Background
Source GDJ
Prismatic Groovy Concentric Background 2 No Black
Source GDJ
This one is amazing, truly original. Go use it!
Source Viahorizon
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
8 by 8 pixels, and just what the title says.
Source pixilated
This light blue background pattern is quite pleasing to the eye, it consists of a tiny rough grid pattern, which is seamless by design. That's it, if you like the color, you can use this seamless pattern in a web design without making any further modifications to it.
Source V. Hartikainen
Lovely light gray floral motif with some subtle shades.
Source GraphicsWall