Prismatic Curved Diamond Pattern No Background@2X #537
 Diamond  CC 0

Prismatic Curved Diamond Pattern No Background

Source GDJ

 More Textures
Retro Circles Background 4 #420
 Dark  CC 0

Retro Circles Background 4

Source GDJ

Background pattern 308 (colour 3) #1870
 Colorful  CC 0

Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.

Source Firkin

Retro Squares Background 7 #397
 Noise  CC 0

Retro Squares Background 7

Source GDJ

Ravenna@2X #355
 Wall  CC BY-SA 3.0

I guess this is inspired by the city of Ravenna in Italy and its stone walls.

Source Sentel

Background pattern 253 #2153
 Brown  CC 0

A seamless pattern created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.

Source Firkin

Prismatic Groovy Concentric Background 2@2X #454
 Noise  CC 0

Prismatic Groovy Concentric Background 2

Source GDJ

Fabric pattern 3 (colour 3) #2385
 Fabric  CC 0

Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Background pattern 9 (colour) #214
 Noise  CC 0

Colour version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net

Source Firkin

Polaroid #187
 Wall  CC BY-SA 3.0

Smooth Polaroid pattern with a light blue tint.

Source Daniel Beaton

Subtle Freckles #89
 Light  CC BY-SA 3.0

This is so subtle: We’re talking 1% opacity. Get your squint on!

Source Atle Mo

Pattern cleanup filtered 2 #152
 Noise  CC 0

Cleanup with gradients and filtering.

Source Lazur URH