Moss 1 #2104
 Unknow  CC 0

CC0 textures, backgrounds.

Source SliverKnight

 More Textures
Leafy frame 31 #1726
 Green  CC 0

A frame using leaves from an image that was uploaded to Pixabay by mayapujiati

Source Firkin

Stone Wall & Gray #1498
 Stone  CC 0

Incoming catena. Stone & well. CC0 texture.

Source Unknow

Hibiscus Flowers Seamless Background #229
 Fabric  CC 0

PDP

Source GDJ

Prismatic Curved Diamond Pattern 6 No [email protected] #546
 Dark  CC 0

Prismatic Curved Diamond Pattern 6 No Background

Source GDJ

Background pattern 309 (colour 4) #1863
 Green  CC 0

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

Source Firkin

Carbon Fiber v2 #105
 Carbon  CC BY-SA 3.0

One more updated pattern. Not really carbon fiber, but it’s the most popular pattern, so I’ll give you an extra choice.

Source Atle Mo

Floral design 97 #1778
 Yellow  CC 0

From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.

Source Firkin

Gradient Squares #693
 Grid  CC BY-SA 3.0

It’s big, it’s gradient—and it’s square.

Source Brankic1979

Greek key pattern 5 #2294
 Dark  CC 0

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

Source Firkin

Through Pixel Dream #1228
 Yellow  CC BY-SA 3.0

A yellow tiled background... Blurriness, bokeh effect and rectangles pattern in one mix.

Source V. Hartikainen

Background pattern 227 (colour 4) #2311
 Green  CC 0

A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.

Source Firkin

Escheresque Dark #1064
 Dark  CC BY-SA 3.0

A comeback for you: the popular Escheresque, now in black.

Source Patten

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 215 (colour 3) #2369
 Pink  CC 0

A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.

Source Firkin

Retro Squares Background [email protected] #798
 Noise  CC 0

Retro Squares Background 6

Source GDJ

Sponge A2-5 #2128
 Wall  CC 0

CC0 textures, backgrounds.

Source SliverKnight

[email protected] #289
 Light  CC BY-SA 3.0

Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!

Source Carolynne

Sewn Stripes Pattern #964
 Stripes  CC BY-SA 3.0

A seamless pattern of "sewn stripes" colored in light gray.

Source V. Hartikainen

Wood 11 #1456
 Wood  CC 0

Gamedev - Wood Textures. CC0 License.

Source Davit Masia

Retro Squares Background [email protected] #419
 Dark  CC 0

Retro Squares Background 4

Source GDJ

Gray [email protected] #914
 Light  CC BY-SA 3.0

Some more diagonal lines and noise, because you know you want it.

Source Atle Mo

Gray Dark #1238
 Gray  CC BY-SA 3.0

Free cc0, hope you will like!

Source SliverKnight

Floral design 98 #1783
 Dark  CC 0

From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.

Source Firkin

Finery #1369
 Unknow  CC 0

Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!

Source Linolafett

Prismatic Abstract Geometric Background 5 No [email protected] #792
 Noise  CC 0

Prismatic Abstract Geometric Background 5 No Black

Source GDJ

"Green Rhombuses", Seamless Background Pattern #1336
 Green  CC BY-SA 3.0

A free green background pattern with a pattern of rhombuses on a seamless texture. Feel free to use it as a tiled background image on your web site.

Source V. Hartikainen

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

Prismatic Floral Background No Black

Source GDJ

Flower pattern 2 #160
 Noise  CC 0

With a gold filter.

Source Lazur URH