CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
A textured blue background pattern with vertical stripes.
Source V. Hartikainen
Here's an yet another seamless note paper texture for use as a background on websites.
Source V. Hartikainen
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
This one is amazing, truly original. Go use it!
Source Viahorizon
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
From a drawing in 'Two Women in the Klondike', Mary Hitchcock, 1899.
Source Firkin
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen
Fix and cc0 to get the tile this is based on.
Source SliverKnight
Nicely crafted paper pattern, although a bit on the large side (500x593px).
Source Blaq Annabiosis
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The image depicts a shell seamless pattern.I used an OCAL clipart called "Shell" uploaded by "jgm104".Thanks.
Source Yamachem
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
A bit strange this one, but nice at the same time.
Source Diogo Silva
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
Derived from a corner decoration itself found as a jpg on Pixabay.
Source Firkin