A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
Same classic 45-degree pattern, dark version.
Source Luke McDonald
A seamless background tile of aged paper with shabby look.
Source V. Hartikainen
Retro Circles Background 7 No Black
Source GDJ
Otis Ray Redding was an American soul singer-songwriter, record producer, arranger, and talent scout. So you know.
Source Thomas Myrman
Stefan is hard at work, this time with a funky pattern of squares.
Source Stefan Aleksić
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.
Source Etienne Rallion
First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.
Source Atle Mo
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
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
The tile this is formed from can be retrieved in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
One more sharp little tile for you. Subtle circles this time.
Source Blunia
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin