Did some testing with Repper Pro tonight, and this gray mid-tone pattern came out.
Source Atle Mo
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
A simple circle. That’s all it takes. This one is even transparent, for those who like that.
Source Saqib
Inspired by a drawing seen in 'City of Liverpool', James Picton, 1883.
Source Firkin
Prismatic Floral Background No Black
Source GDJ
Remixed from a drawing in 'A Child of the Age', Francis Adams, 1894.
Source Firkin
Zero CC tileable ground (#2) cracked, crackled texture, made by me. CC0
Source Sojan Janso
Same as the black version, but now in shades of gray. Very subtle and fine grained.
Source Atle Mo
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
One more brick pattern. A bit more depth to this one.
Source Benjamin Ward
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
Prismatic Curved Diamond Pattern No Background
Source GDJ
Zero CC tileable cork floor, photographed and made by me. CC0
Source Sojan Janso
A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
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
Seamless Olive Green Web Background Image
Source V. Hartikainen
You know you love wood patterns, so here’s one more.
Source Richard Tabor
Here's a new paper-like background for free use on personal and commercial projects (this applies to all background patterns here).
Source V. Hartikainen
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Background formed from the original with an emboss effect
Source GDJ
Background pattern made in "Grunge-Like" style. Available in both SVG and JPG formats. Edit to your needs then click the download button.
Source V. Hartikainen
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
Sometimes you just need the simplest thing.
Source Fabricio
Seamless tile drawn in Paint.net and vectorised in Vector Magic.
Source Firkin