Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
No relation to the band, but damn it’s subtle!
Source Thomas Myrman
Farmer could be some sort of fabric pattern, with a hint of green.
Source Fabian Schultz
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
Little x’es, noise and all the stuff you like. Dark like a Monday, with a hint of blue.
Source Tom McArdle
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.
Source Josh Green
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin
Prepared mostly as a raster in Paint.net and vectorised.
Source Firkin
An aged paper background tile with smeared and pressed text.
Source V. Hartikainen
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
A repeating background of beige paper with vintage look. Repeats to infinity, as usual.
Source V. Hartikainen
No, not the band but the pattern. Simple squares in gray tones, of course.
Source Atle Mo
A free green background pattern with a pattern of rhombuses on a seamless texture. Feel free to use it as a tiled background image on your web site.
Source V. Hartikainen
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
The base gradient edited so now more details are rendered.
Source Lazur URH
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Here's a repeatable texture that resembles a light green concrete wall or something similar.
Source V. Hartikainen
This is a remix of "blue wave-seigaiha".I hope this subtle color version of Seigaiha would be suitable for background .
Source Yamachem
Derived from a drawing in 'Elfrica. An historical romance of the twelfth century', Charlotte Boger, 1885
Source Firkin
Zero CC tileable wood texture, made by me procedurally in Neo Texture Edit.
Source Sojan Janso