This was formed by distorting an image of a background on Pixabay.
Source Firkin
Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.
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
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Hexagonalism Pattern No Background
Source GDJ
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A re-make of the Gradient Squares pattern.
Source Dimitar Karaytchev
A seamless paper background texture colored in pale yellow. This seamless texture is ideal for those who need a yellow background image for their website. The texture resembles paper.
Source V. Hartikainen
Prismatic Hypnotic Pattern No Background
Source GDJ
Zero CC tileable ground (#2) cracked, crackled texture, made by me. CC0
Source Sojan Janso
A seamless pattern the starting point for which was a 'light rays' rendering in Paint.net.
Source Firkin
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Background Wall, Art Abstract, white Well & CC0 texture.
Source Ractapopulous
To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Abstract Geometric Background 5 No Black
Source GDJ
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
A light background pattern with diagonal stripes. Here's a simple light striped background for you.
Source V. Hartikainen