I skipped number 3, because it wasn’t all that great. Sorry.
Source Dima Shiper
This is the remix of an OCAL clipart called "Rain on Window" uploaded by "pagarmidna".Thanks.This is a seamless pattern of raindrops.
Source Yamachem
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
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
A pattern formed from a photograph of a 16th century ceramic tile.
Source Firkin
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Remixed from a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
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
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The tile this is based on was adapted from an image that was uploaded to Pixabay by frolicsomepl. It can be had in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
There are quite a few grid patterns, but this one is a super tiny grid with some dust for good measure.
Source Dominik Kiss
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A background tile of dark textile. Made this a long time ago and just now decided to publish it.
Source V. Hartikainen
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
A blue gray fabric-like texture for websites. An yet another fabric-like texture. It has subtle vertical and diagonal stripes to it.
Source V. Hartikainen
Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.
Source Etienne Rallion
This is indeed a bit strange, but here’s to the crazy ones!
Source Christopher Buecheler