From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
The tile this is formed from can be retrieved in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
Inspired by a pattern seen on a public domain image of a very old tile. To get the unit cell, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf
The tile this is based on was adapted from an image that was uploaded to Pixabay by frolicsomepl. It can be had in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
A seamless background pattern with impressed gray dots.
Source V. Hartikainen
I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
A browner version of the original weathered fence texture.
Source Firkin
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Looks like an old wall. I guess that’s it then?
Source Viahorizon
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 free grid paper background pattern for using on web sites.
Source V. Hartikainen
From an image on opengameart.org shared by rubberduck.
Source Firkin
Alternative colour scheme for the original floral pattern.
Source Firkin
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ