Concrete Wall 2 #79
 Wall  CC BY-SA 3.0

A light gray wall or floor (you decide) of concrete.

Source Atle Mo

 More Textures
Abstract Arbitrary Geometric [email protected] #498
 Noise  CC 0

Abstract Arbitrary Geometric Background derived from an image on Pixabay.

Source GDJ

Wavy background #2023
 Pink  CC 0

CC0 and a seamless pattern from a tile drawn in Paint.net .

Source SliverKnight

Spiral pattern 2 (colour) #2174
 Red  CC 0

A seamless pattern drawn in Inkscape.

Source Firkin

Concretia 5 #1412
 Gray  CC 0

Gamedev - Concrete Textures. CC0 License.

Source Davit Masia

Patern dots #241
 Dark  CC 0

Pattern repeating background 48x48

Source Keistutis

Background pattern 315 (colour 6) #1840
 Green  CC 0

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

Source Firkin

SubtleNet #855
 Light  CC BY-SA 3.0

You can never get enough of these tiny pixel patterns with sharp lines.

Source Designova

Page ornament 41 #2092
 Dark  CC 0

Derived from a drawing in 'The Murmur of the Shells', Samuel Cowen, 1879.

Source Firkin

Stone Wall & Gray #1486
 Stone  CC 0

Incoming catena. Stone & well. CC0 texture.

Source Unknow

Batthern #324
 Grid  CC BY-SA 3.0

Sometimes simple really is what you need, and this could fit you well.

Source Factorio.us Collective

Ravenna #354
 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 312 (colour 2) #1859
 Red  CC 0

Alternative colour scheme

Source Firkin

Subtle Grunge #1040
 Light  CC BY-SA 3.0

A heavy hitter at 400x400px, but lovely still.

Source Breezi

Gray Sand #17
 Dark  CC BY-SA 3.0

A dark gray, sandy pattern with small light dots, and some angled strokes.

Source Atle Mo

Background pattern 201 #2501
 Grid  CC 0

A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.

Source Firkin

Wood #49
 Wood  CC BY-SA 3.0

Dark wooden pattern, given the subtle treatment. based on texture from Cloaks.

Source Atle Mo
Based from Cloaks

Grid Paper Background (Blue Gray) #1162
 Grid  CC BY-SA 3.0

A free grid paper background pattern for using on web sites.

Source V. Hartikainen

Background pattern purple #1998
 Colorful  CC 0

Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin

Stone Wall & Purple #1541
 Stone  CC 0

Incoming catena. Stone & well. CC0 texture.

Source Unknow

Floral background 16 #1914
 Dark  CC 0

Floral background 16

Source Firkin

Light Brown Wallpaper With Vertical Stripes #905
 Stripes  CC BY-SA 3.0

This seamless light brown background texture resembles a wallpaper with vertical stripes. One way to use it is as a tiled background on web sites.

Source V. Hartikainen

Nice Snow #1199
 Light  CC BY-SA 3.0

Not the most subtle, but very useful.

Source Kerstkaarten

Background pattern 235 (colour 2) #2254
 Blue  CC 0

To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Background pattern 224 (colour 6) #2337
 Colorful  CC 0

To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Prismatic Abstract Geometric Background [email protected] #793
 Noise  CC 0

Prismatic Abstract Geometric Background 5

Source GDJ

Floors & Block #1603
 Wall  CC 0

Floors-Tiles. CC0 License.

Source Unknow

Stylized lion design #2089
 Dark  CC 0

Derived from a drawing in 'Historiske Afhandlinger', Adolf Jorgensen, 1898.

Source Firkin

White [email protected] #369
 Wall  CC BY-SA 3.0

Sweet and subtle white plaster with hints of noise and grunge.

Source Phil Maurer

Stone Wall & Green #1534
 Stone  CC 0

Incoming catena. Stone & well. CC0 texture.

Source Unknow

Retro Squares Background [email protected] #799
 Dark  CC 0

Retro Squares Background 5

Source GDJ