This background has abstract texture with some similarities to wood.
Source V. Hartikainen
A dark metal plate with an embossed grid pattern and a bit of rust. Here's a dark metal plate texture for use as a tiled background on web pages.
Source V. Hartikainen
From an image on opengameart.org shared by rubberduck.
Source Firkin
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Light gray pattern with an almost wall tile-like appearance.
Source Markus Tinner
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
This ladies and gentlemen, is texturetastic! Love it.
Source Adam Pickering
This is a seamless pattern which is derived from a flower petal image.
Source Yamachem
From a drawing in 'Worsborough; its historical associations and rural attractions', Joseph Wilkinson, 1879.
Source Firkin
This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
Colorful Floral Background 3 No Black
Source GDJ
The image depicts a Japanese Edo pattern called "kanoko or 鹿の子" meaning "fawn" which has a fur with small white spots.
Source Yamachem
Prismatic Polka Dots Mark II 3 No Background
Source GDJ
A very dark spotted twinkle pattern for your twinkle needs.
Source Badhon Ebrahim
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Zero CC tileable bark texture, photographed and made by me. CC0
Source Sojan Janso
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
Small gradient crosses inside 45-degree boxes, or bigger crosses if you will.
Source Wassim