Prepared mostly as a raster in Paint.net and vectorised.
Source Firkin
From a drawing in 'Less Black than we're painted', James Payn, 1884.
Source Firkin
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
Same classic 45-degree pattern, dark version.
Source Luke McDonald
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
Nasty or not, it’s a nice pattern that tiles. Like they all do.
Source Badhon Ebrahim
Zero CC tileable seed texture, edited by me to be seamless from a Pixabay image. CC0
Source Sojan Janso
Did some testing with Repper Pro tonight, and this gray mid-tone pattern came out.
Source Atle Mo
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Here's a bluish gray striped background pattern for use on web sites.
Source V. Hartikainen
Retro Circles Background 4 No Black
Source GDJ
Prismatic Geometric Tessellation Pattern No Background
Source GDJ
A textured orange background pattern with vertical stripes.
Source V. Hartikainen
Could be paper, could be a Polaroid frame – up to you!
Source Chaos
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
More leather, and this time it’s bigger! You know, in case you need that.
Source Elemis
A playful triangle pattern with different shades of gray.
Source Dimitrie Hoekstra
The image depicts a seamless pattern which includes hexagonally-aligned gourds with BG in light-brown.
Source Yamachem
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin