Seamless pattern made from a tile that can be obtained in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A free seamless texture of reptile skin colored in a dark brown color. As always, you may use it as a repeated background image in your web design works, or for any other purposes.
Source V. Hartikainen
Derived from a drawing in 'The Murmur of the Shells', Samuel Cowen, 1879.
Source Firkin
Remixed from an image that was uploaded to Pixabay by CatherineClennan
Source Firkin
Light and tiny, just the way you like it.
Source Rohit Arun Rao
ZeroCC tileable beechwood wood texture, generated in Neo Texture Edit by me. CC0
Source Sojan Janso
From a drawing in 'A Guide to the Guildhall of the City of London', John Baddeley, 1898.
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
Produced using the clouds, flames and glass blocks plug-ins in Paint.net and the resulting .PNG vectorised with Vector Magic.
Source Firkin
Prismatic Abstract Line Art Pattern Background
Source GDJ
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Retro Circles Background 8 No Black
Source GDJ
If you don’t like cream and pixels, you’re in the wrong place.
Source Mizanur Rahman
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Hey, you never know when you’ll need a bird pattern, right?
Source Pete Fecteau
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
One more from Badhon, sharp horizontal lines making an embossed paper feeling.
Source Badhon Ebrahim