Diamond pattern (colour 4) #2282
 Blue  CC 0

From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

 More Textures
Ribbon pattern 2 (version 2) #2039
 Colorful  CC 0

The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Background pattern 246 (colour 2) #2185
 Green  CC 0

This was formed by distorting an image of a background on Pixabay.

Source Firkin

Bright Squares #87
 Light  CC BY-SA 3.0

It’s okay to be square! A nice light gray pattern with random squares.

Source Waseem Dahman

Background pattern 320 (colour 2) #1829
 Dark  CC 0

Formed by distorting a JPG from PublicDomainPictures

Source Firkin

Worn Out Cardboard #1214
 Cardboard  CC BY-SA 3.0

A seamless texture of worn out "cardboard".

Source V. Hartikainen

Retro Circles Background 4 #420
 Dark  CC 0

Retro Circles Background 4

Source GDJ

Wood Chips 5 #2103
 Unknow  CC 0

CC0 textures, backgrounds.

Source SliverKnight

Background pattern 313 #1858
 Dark  CC 0

Background pattern originally a PNG drawn in Paint.net

Source Firkin

Floral background 10 (colour 2) #2045
 Pink  CC 0

Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.

Source Firkin

Background pattern 334 (colour 2) #1731
 Yellow  CC 0

Derived from an image that was uploaded to Pixabay by Kaz

Source Firkin

Dark Wall #817
 Dark  CC BY-SA 3.0

Just to prove my point, here is a slightly modified dark version.

Source Atle Mo

"Colorful Stripes", Diagonally Striped Background #903
 Stripes  CC BY-SA 3.0

This background pattern contains worn out colorful stripes as a texture.

Source V. Hartikainen

Stone Wall & Dark #1538
 Stone  CC 0

Incoming catena. Stone & well. CC0 texture.

Source Unknow

Floors & Black #1607
 Wall  CC 0

Floors-Tiles. CC0 License.

Source Unknow

[email protected] #952
 Gray  CC BY-SA 3.0

A large pattern with funky shapes and form. An original. Sort of origami-ish.

Source Luuk van Baars

Prismatic Floral Background No [email protected] #476
 Light  CC 0

Prismatic Floral Background No Black

Source GDJ

Background pattern 336 (colour 2) #1720
 Green  CC 0

Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.

Source Firkin

Background Patterns - Ebony #249
 Fabric  CC 0

If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117

Source Viscious-Speed

Dark [email protected] #122
 Dark  CC BY-SA 3.0

Small dots with minor circles spread across to form a nice mosaic.

Source John Burks

Retro Circles Background 8 No [email protected] #438
 Dark  CC 0

Retro Circles Background 8 No Black

Source GDJ

Seamless tile 4 #1812
 Red  CC 0

Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern

Source Firkin

Background pattern 308 (colour 5) #1869
 Blue  CC 0

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

Source Firkin

Light Honeycomb #59
 Light  CC BY-SA 3.0

Light honeycomb pattern made up of the classic hexagon shape.

Source Federica Pelzel

Electric recharge #163
 Noise  CC 0

Simple turbulence filter rigged in in inkscape.

Source Lazur URH

Door Rail & Black #1625
 Dark  CC 0

Manmade & Civilisation-Details. CC0 License.

Source Unknow

"Honeycomb", Orange Background Pattern #1313
 Orange  CC BY-SA 3.0

The following orange background pattern resembles a honeycomb.

Source V. Hartikainen

Floral background 18 (negative) #1832
 Dark  CC 0

Negative version of the original

Source Firkin