I guess this is inspired by the city of Ravenna in Italy and its stone walls.
Source Sentel
Remixed from a drawing that was uploaded to Pixabay by DavidZydd
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Prismatic Curved Diamond Pattern 5 No Background
Source GDJ
Remixed from a drawing in 'Prehistoric Man: researches into the origin of civilisation in the old and the new world', Daniel Wilson, 1876.
Source Firkin
Feel free to download this "Dark Wood" background texture for your web site. The background tiles seamlessly!
Source V. Hartikainen
Kaleidoscope Prismatic Abstract No Background
Source GDJ
Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!
Source Dertig Media
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Remixed from a JPG that was uploaded to Pixabay by theasad121
Source Firkin
This one is amazing, truly original. Go use it!
Source Viahorizon
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
Black brick wall pattern. Brick your site up!
Source Alex Parker
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Seamless Prismatic Geometric Pattern With Background
Source GDJ
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
Utilising a bird from s-light and some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
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
From a drawing in 'A Rolling Stone. A tale of wrongs and revenge', John Hartley, 1878.
Source Firkin
Different from the original in being a simple tile stored as a pattern definition, rather than numerous repeated objects. Hence easy and quick to give this pattern to objects of different shapes. To get the tile in Inkscape, select the rectangle and use shift+alt+i.
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