From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The image depicts a seamless pattern of a tortoise in tortoiseshell (hexagon).
Source Yamachem
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
This is a hot one. Small, sharp and unique.
Source GraphicsWall
Prismatic Snowflakes Pattern 3 No Background
Source GDJ
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
There are many carbon patterns, but this one is tiny.
Source Designova
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
An alternative colour scheme for the original background.
Source Firkin
An alternative colour scheme to the original seamless pattern.
Source Firkin
Prismatic Polka Dots Mark II 2 No Background
Source GDJ
Derived from a PNG that was uploaded to Pixabay by nutkitten
Source Firkin
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
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
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
Prismatic Geometric Pattern Background 2
Source GDJ
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