A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Prismatic Triangular Background Design Mark II 5
Source GDJ
Sometimes you just need the simplest thing.
Source Fabricio
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
This background pattern looks like bamboo to me. Feel free to download it for your website (for your blog perhaps?).
Source V. Hartikainen
This was submitted in a beige color, hence the name. Now it’s a gray paper pattern.
Source Konstantin Ivanov
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
Abstract Tiled Background Extended 10
Source GDJ
A simple circle. That’s all it takes. This one is even transparent, for those who like that.
Source Saqib
A series of 5 patterns. That’s what the P stands for, if you didn’t guess it.
Source Dima Shiper
There are quite a few grid patterns, but this one is a super tiny grid with some dust for good measure.
Source Dominik Kiss
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
A green background pattern with warped vertical stripes and a grunge look.
Source V. Hartikainen
A web texture of brown canvas. Will look great, when used in dark web designs.
Source V. Hartikainen
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
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
With a name this awesome, how can I go wrong?
Source Nikolay Boltachev
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
This was formed by distorting an image of a background on Pixabay.
Source Firkin