From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Prismatic Isometric Cube Wireframe Pattern No Background
Source GDJ
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
Feel free to download this "Dark Wood" background texture for your web site. The background tiles seamlessly!
Source V. Hartikainen
Smooth Polaroid pattern with a light blue tint.
Source Daniel Beaton
Hexagonal dark 3D pattern. What more can you ask for?
Source Norbert Levajsics
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
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
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman
As far as fabric patterns goes, this is quite crisp.
Source Heliodor Jalba
The tile this is formed from can be retrieved in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Prismatic Groovy Concentric Background
Source GDJ
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Prismatic Triangular Background Design Mark II 5
Source GDJ
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Fabric-ish patterns are close to my heart. French Stucco to the rescue.
Source Christopher Buecheler
Super detailed 16×16 tile that forms a beautiful pattern of straws.
Source Pavel
It’s an egg, in the form of a pattern. This really is 2012.
Source Paul Phönixweiß