Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.
Source Firkin
This one has rusty dark brown texture.
Source V. Hartikainen
Prismatic Groovy Concentric Background 4
Source GDJ
A seamless pattern based on a tile that can be achieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The tile for this is based on a repeating unit close to a design on Pixabay. It can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
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
Pass parameters to the URL or edit the source code variables to configure the graph paper for the division desired.
Source JayNick
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Abstract Geometric Background 4
Source GDJ
A free seamless background image with abstract texture of green "curtain".
Source V. Hartikainen
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A floral background formed from numerous clones of flower 117.
Source Firkin
Pattern that came out of playing with the 'slinky' plug-in for Paint.net
Source Firkin
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
Tile available in Inkscape using shift-alt-i on the selected rectangle
Source Firkin
If you don’t like cream and pixels, you’re in the wrong place.
Source Mizanur Rahman
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
One more from Badhon, sharp horizontal lines making an embossed paper feeling.
Source Badhon Ebrahim
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
One more sharp little tile for you. Subtle circles this time.
Source Blunia
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
A free seamless background texture that looks like a brown stone wall.
Source V. Hartikainen