From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Honestly, who does not like a little pipe and mustache?
Source Luca Errico
Inspired by a drawing in 'Kulturgeschichte', Freidrich Hellwald, 1896.
Source Firkin
Bit of a strange name on this one, but still nice. Tiny gray square things.
Source Carlos Valdez
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
I took the liberty of using Dmitry’s pattern and made a version without perforation.
Source Atle Mo
I’m starting to think I have a concrete wall fetish.
Source Atle Mo
Prismatic Abstract Geometric Background derived from an image on Pixabay.
Source GDJ
A car pattern?! Can it be subtle? I say yes!
Source Radosław Rzepecki
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Seamless Green Tile Background
Source V. Hartikainen
The image depicts a seamless pattern of pine tree leaves.
Source Yamachem
Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i
Source Firkin
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
Sharp pixel pattern, just like the good old days.
Source Paridhi
This seamless web background texture looks like gray stone. It's great for using as a background image on web pages, or on some of their elements. Anyway, I hope you will find use for it.
Source V. Hartikainen