The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Remixed from a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Bit of a strange name on this one, but still nice. Tiny gray square things.
Source Carlos Valdez
A mid-tone gray pattern with some cement looking texture.
Source Hendrik Lammers
Sometimes you just need the simplest thing.
Source Fabricio
From a drawing in 'Hundert Jahre in Wort und Bild', S. Stefan, 1899.
Source Firkin
Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
This background pattern contains a texture of yellow wood planks. I think it looks quite original.
Source V. Hartikainen
The base gradient edited so now more details are rendered.
Source Lazur URH
A floral background formed from numerous clones of flower 117.
Source Firkin
A seamless web texture of "green stone".
Source V. Hartikainen
Prismatic Abstract Geometric Background 2 No Black
Source GDJ
Wasn't satisfied with the original's colouring. Too much component transfer and colormatrixes yet the results are lacking a bit. So this time it is a simple black to transparent fade, making it possible remixing easily once there will be other blending modes supported as well. Probably in inkscape 0.92.
Source Lazur URH
A colourful background drawn originally in paint.net and vectorised in Vector Magic.
Source Firkin