CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
This background pattern has futuristic look. So, maybe it could be used on websites or blogs dedicated to video games?!
Source V. Hartikainen
A brown seamless wood texture in a form of stripe pattern. The result has turned out pretty well, in my opinion.
Source V. Hartikainen
ZeroCC tileable moss texture, photographed and made by me. CC0
Source Sojan Janso
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From a drawing in 'Handbook of the excursions proposed to be made by the Lincoln Diocesan Architectural Society, on the 27th and 28th of May, 1857', Edward Trollope, 1857.
Source Firkin
You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman
A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.
Source Firkin
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
The edges of all the red objects line up either vertically or horizontally, but it doesn't appear so. Made from a square tile that can be got by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A background pattern with a look of rough fabric.
Source V. Hartikainen
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
If you don’t like cream and pixels, you’re in the wrong place.
Source Mizanur Rahman
Here's a subtle marble-like background for use on websites.
Source V. Hartikainen
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
This is a hot one. Small, sharp and unique.
Source GraphicsWall
A background pattern with green vertical stripes. A new striped background pattern. This time a green one.
Source V. Hartikainen
Derived from a PNG that was uploaded to Pixabay by nutkitten
Source Firkin