From a drawing in 'Artists and Arabs', Henry Blackburn, 1868.
Source Firkin
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
Lovely pattern with some good-looking non-random noise lines.
Source Zucx
Like the name suggests, this background image consists of a pattern of dark bricks. It may be an option for you, if you are looking for something that looks like a brick wall for use as a background on web pages. It's not a masterpiece, but looks pretty nice when is tiled.
Source V. Hartikainen
A bit like smudged paint or some sort of steel, here is scribble light.
Source Tegan Male
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
This one needs to be used in small areas; you can see it repeat.
Source Luca
Sharp but soft triangles in light shades of gray.
Source Pixeden
This seamless pattern consists of a blue grid on a yellow background.
Source V. Hartikainen
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
The image is a remix of "edo pattern-samekomon".I changed the color of dots from black to white and added BG in light-yellow.
Source Yamachem
This background image is great for using in web design or graphic design projects. And don't forget to visit the homepage. I frequently update this resource with fresh tileable backgrounds.
Source V. Hartikainen
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
Derived from an image that was uploaded to Pixabay by mdmelo.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Prismatic Snowflakes Pattern 2 No Background
Source GDJ
Psychedelic Geometric Background No Black
Source GDJ
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
Zero CC bark from fur tree tileable texture, photographed and made by me. CC0
Source Sojan Janso