From a drawing of the coat of arms of the Ottoman Empire on Wikimedia.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
You know you can’t get enough of these linen-fabric-y patterns.
Source James Basoo
Prismatic Floral Pattern 3 Variation 3 No Background
Source GDJ
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Background Wall, Art Abstract, Blue Well & CC0 texture.
Source Ractapopulous
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Adapted from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Zero CC tileable hard cover cells book texture, 4k, scanned and made by me. CC0
Source Sojan Janso
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Prismatic Geometric Tessellation Pattern 4 No Background
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 unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
8 by 8 pixels, and just what the title says.
Source pixilated
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen
Remixed from a drawing in 'Works. Popular edition', John Ruskin, 1886.
Source Firkin
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
From a drawing in 'Hundert Jahre in Wort und Bild', S. Stefan, 1899.
Source Firkin