A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Formed from decorative divider 184 in paint.net. Vectorised with Vector Magic.
Source Firkin
Colour version of the original pattern inspired by the front cover of 'Old and New Paris', Henry Edwards, 1894.
Source Firkin
Prismatic Abstract Background Design No Black
Source GDJ
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
Same as Silver Scales, but in black. Turn your site into a dragon with this great scale pattern.
Source Alex Parker
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Prismatic Floral Background No Black
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
Zero CC tileable yellow craft paper; scanned and made by me. CC0
Source Sojan Janso
Prismatic Polka Dots Mark II No Background
Source GDJ
Inspired by a pattern found in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
A seamless tessellation pattern. To get the tile this is formed from, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
Luxury pattern, looking like it came right out of Paris.
Source Daniel Beaton
A version without colours blended together to give a different look.
Source Firkin
This seamless pattern consists of a blue grid on a yellow background.
Source V. Hartikainen
I have no idea how to describe this one, but it’s light and delicate.
Source JBasoo
A seamless background pattern with impressed gray dots.
Source V. Hartikainen
A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.
Source Lazur URH
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers