From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
The image depicts a seamless pattern of a snow crystal.I referred to a book called ”sekka-zusetsu” or "雪華図説" which means an illustrated explanation about snow crystals.This book was published in 1832 (天保3年) or Edo period.For more about "雪華図説",see here:dl.ndl.go.jp/info:ndljp/pid/2536975
Source Yamachem
A seamless pattern formed from background pattern 102
Source Firkin
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A light background pattern with diagonal stripes. Here's a simple light striped background for you.
Source V. Hartikainen
Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
Original seamless pattern with an Inkscape filter.
Source Firkin
A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, 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
This one is something special. I’d call it a flat pattern, too. Very well done, sir!
Source GetDiscount
A dark brown fabric-like background texture with seamless pattern of winding stripes.
Source V. Hartikainen
Zero CC tileable hard cover cells book texture, 4k, scanned and made by me. CC0
Source Sojan Janso
This one resembles a black concrete wall when is tiled. It should look great, at least with dark website themes.
Source V. Hartikainen
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Snap! It’s a pattern, and it’s not grayscale! Of course you can always change the color in Photoshop.
Source Atle Mo
A bit strange this one, but nice at the same time.
Source Diogo Silva
More leather, and this time it’s bigger! You know, in case you need that.
Source Elemis
Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida