Retro Squares Background 2@2X #417
 Noise  CC 0

Retro Squares Background 2

Source GDJ

 More Textures
Prismatic Pointers Background #388
 Noise  CC 0

Prismatic Pointers Background

Source GDJ

Dark Brown Leather Texture, Seamless Tile #1092
 Leather  CC BY-SA 3.0

The texture of this background image has some similarities with leather, and it's colored in a dark brown color. So, if you are looking for a dark brown background image for your website, this may be an option for you.

Source V. Hartikainen

Nami #575
 Dark  CC BY-SA 3.0

Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!

Source Dertig Media

Floral design 71 #2429
 Dark  CC 0

From a drawing in 'From Snowdon to the Sea. Striking stories of North and South Wales', Marie Trevelyan, 1895.

Source Firkin

Gun Metal #360
 Dark  CC BY-SA 3.0

With a name this awesome, how can I go wrong?

Source Nikolay Boltachev

Snowflake pattern remix #156
 Dark  CC 0

The base gradient edited so now more details are rendered.

Source Lazur URH