Sounds French. Some 3D square diagonals, that’s all you need to know.
Source Graphiste
Seamless SVG vector and JPG backgrounds with faded diagonal stripes. The colors are editable.
Source V. Hartikainen
Black brick wall pattern. Brick your site up!
Source Alex Parker
Prismatic Snowflakes Pattern 2 No Background
Source GDJ
Seamless pattern inspired by a drawing on Pixabay. To get the tile this is formed from, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.
Source Josh Green
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
This was formed by distorting an image of a background on Pixabay.
Source Firkin
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Floral patterns might not be the hottest thing right now, but you never know when you need it!
Source Lauren
A very slick dark rubber grip pattern, sort of like the grip on a camera.
Source Sinisha
One more sharp little tile for you. Subtle circles this time.
Source Blunia
Inspired by a pattern seen on a public domain image of a very old tile. To get the unit cell, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Remixed from a drawing in 'Some account of the Worshipful Company of Ironmongers', John Nicholl, 1866.
Source Firkin
Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen
A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.
Source V. Hartikainen