Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
Based on an image that was uploaded to Pixabay by devanath
Source Firkin
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
More in the paper realm, this time with fibers.
Source Jorge Fuentes
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Neat little photography icon pattern.
Source Hossam Elbialy
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
The texture of this background image has some similarities with leather, and it's colored in a dark brown color. So, if you are looking for a dark brown background image for your website, this may be an option for you.
Source V. Hartikainen
This one looks like a cork panel. Feel free to use it as a tiled background on your blog or website.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A comeback for you: the popular Escheresque, now in black.
Source Patten
This is so subtle you need to bring your magnifier!
Source Carlos Valdez
An abstract texture of black metal pipes (seamless).
Source V. Hartikainen
Inspired by a pattern seen on a public domain image of a very old tile. To get the unit cell, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Inspired by a 1930s wallpaper pattern I saw on TV.
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
Prismatic Abstract Background Design
Source GDJ
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
A background pattern with wavy green vertical stripes. This one has green stripes on a white background. Download if you like it.
Source V. Hartikainen
Fix and cc0 to get the tile this is based on.
Source SliverKnight