Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
Seamless Light Background Texture.
Source V. Hartikainen
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
This was formed by distorting an image of a background on Pixabay.
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
Nicely crafted paper pattern, although a bit on the large side (500x593px).
Source Blaq Annabiosis
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Not so subtle. These tileable wood patterns are very useful.
Source Elemis
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
A seamless green background texture. The image is distributed under a Creative Commons License (like all of the images here).
Source V. Hartikainen
This is a remix of "flower seamless pattern".I rotated the original image by 90 degrees.This is a seamless pattern of flowers.These horizontal wavy lines are one of Edo patterns which is called "tatewaku or tachiwaku or 立湧" that represents uprising steam or vapor.
Source Yamachem
Number 2 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Seamless Background For Websites. It has a texture similar to cork-board.
Source V. Hartikainen
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
CC0 remixed from a drawing. Walter Crane, 1914, Firkin.
Source SliverKnight
A very slick dark rubber grip pattern, sort of like the grip on a camera.
Source Sinisha
A web texture of brown canvas. Will look great, when used in dark web designs.
Source V. Hartikainen