From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
A seamless textured paper for backgrounds. Colored in pale orange hues.
Source V. Hartikainen
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Inspired by a pattern found in 'A General History of Hampshire, or the County of Southampton, including the Isle of Wight', Bernard Woodwood, 1861
Source Firkin
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Sounds French. Some 3D square diagonals, that’s all you need to know.
Source Graphiste
A free background pattern with abstract green tiles.
Source V. Hartikainen
A seamless web background with texture of aged grid paper.
Source V. Hartikainen
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
A grayscale fabric pattern with vertical lines of stitch holes.
Source V. Hartikainen
From a drawing in 'Uit de geschiedenis der Heilige Stede te Amsterdam', Yohannes Sterck, 1898.
Source Firkin
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
From an image on opengameart.org shared by rubberduck.
Source Firkin
This background pattern contains worn out colorful stripes as a texture.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
CC0 remixed from a drawing. Walter Crane, 1914, Firkin.
Source SliverKnight
Has nothing to do with toast, but it’s nice and subtle.
Source Pippin Lee
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso