Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Zero CC tileable hard cover green book, scanned and made by me. CC0
Source Sojan Janso
Prismatic Polka Dots 3 No Background
Source GDJ
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
A repeating graphic with ancient pattern. I came up with this name/title at last minute, so you may find that there is very little of ancientness in this pattern after all.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This is the remix of "Tileable Wave Pattern 2" uploaded by "Arvin61r58".Thanks.I added a wire-mesh fence seamless pattern as a lower layer.
Source Yamachem
Some more diagonal lines and noise, because you know you want it.
Source Atle Mo
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A black tile-able background with paper-like texture.
Source V. Hartikainen
Remixed from an image on Pixabay, the original having been uploaded by darkmoon1968.
Source Firkin
A simple circle. That’s all it takes. This one is even transparent, for those who like that.
Source Saqib
Formed by distorting a JPG from PublicDomainPictures
Source Firkin
You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
This is a seamless pattern of regular hexagon which has a honeycomb structure.
Source Yamachem