From a drawing in 'Hubert Montreuil, or the Huguenot and the Dragoon', Francisca Ouvry, 1873.
Source Firkin
This is sort of fresh, but still feels a bit old school.
Source Martuchox
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
A free background pattern with abstract green tiles.
Source V. Hartikainen
A seamless pattern formed from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Rounded Squares Grid 4 No Background
Source GDJ
Hexagonal dark 3D pattern. What more can you ask for?
Source Norbert Levajsics
Some dark 45 degree angles creating a nice pattern. Huge.
Source Dark Sharp Edges
A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.
Source Atle Mo
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
Just like the black maze, only in light gray. Duh.
Source Peax
Paper model of a tetrahedron. Modelo de papel de um tetraedro.
Source laobc
The image depicts a seamless pattern made using a bird's face.
Source Yamachem
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim