One more in the line of patterns inspired by Japanese/Asian styles. Smooth.
Source Kim Ruddock
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Derived from a design in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
Sharp but soft triangles in light shades of gray.
Source Pixeden
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Sort of reminds me of those old house wallpapers.
Source Tish
Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Dark blue concrete wall with some small dust spots.
Source Atle Mo
A large (588x375px) sand-colored pattern for your ever-growing collection. Shrink at will.
Source Alex Tapein
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Coming in at 666x666px, this is an evil big pattern, but nice and soft at the same time.
Source Atle Mo
From a drawing in 'Codogno e il suo territorio nella cronaca e nella storia'', Gio and Giarella Cairo, 1897.
Source Firkin
You know you can’t get enough of these linen-fabric-y patterns.
Source James Basoo
Remixed from a raster on Pixabay that was uploaded by ArtsyBee.
Source Firkin
Prismatic Curved Diamond Pattern 2 No Background
Source GDJ
A seamless texture of worn out "cardboard".
Source V. Hartikainen