Here's a camo print with more tan and less green, such as might be used in a desert scenario. This is tileable, so it can be used as a wallpaper or background.
Source Eady
Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
Here's a seamless brown cork board background texture. Feel free to download or reshare if you like.
Source V. Hartikainen
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
Bright Multicolored Floral Background by Karen Arnold from PDP.
Source GDJ
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
Geometric triangles seem to be quite hot these days.
Source Pixeden
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
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 seamless canvas texture for using as background on websites. Colored in pale tones of brown.
Source V. Hartikainen
From a drawing in 'Artists and Arabs', Henry Blackburn, 1868
Source Firkin
Prismatic Curved Diamond Pattern 6 No Background
Source GDJ
Sounds French. Some 3D square diagonals, that’s all you need to know.
Source Graphiste
Seamless Background For Websites. It has a texture similar to cork-board.
Source V. Hartikainen
Original minus the background
Source Firkin
The image is the remix of "wire-mesh fence seamless pattern" .This is a more minute version of it.Sorry for the file size.Using path>difference in Inkscape, I will cut out any silhouette from this pattern and create a "meshed silhouette".
Source Yamachem
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
This is so subtle you need to bring your magnifier!
Source Carlos Valdez
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
I know there is one here already, but this is sexy!
Source Gjermund Gustavsen