The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
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
Zero CC tileable Crackled Cement (streaks) texture, photographed and made by me. CC0
Source Sojan Janso
Nicely crafted paper pattern, although a bit on the large side (500x593px).
Source Blaq Annabiosis
More bright luxury. This is a bit larger than fancy deboss, and with a bit more noise.
Source Viszt Péter
Used the 6th circle pattern designed by Viscious-Speed to create a print that can be used for card making or scrapbooking. Save as a PDF file for the best printing option.
Source Lovinglf
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
On a large canvas you can see it tiling, but used on smaller areas, it’s beautiful.
Source Paul Phönixweiß
Black paper texture, based on two different images.
Source Atle Mo
Based from Design Kindle
Derived from a drawing in 'Elfrica. An historical romance of the twelfth century', Charlotte Boger, 1885
Source Firkin
I have no idea how to describe this one, but it’s light and delicate.
Source JBasoo
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
A free repetitive background with a dark concrete wall like texture. This one may be used in dark web site designs.
Source V. Hartikainen
Prismatic Curved Diamond Pattern 6 No Background
Source GDJ
Might not be super subtle, but quite original in its form.
Source Alex Smith
Zero CC tileable ground (#2) cracked, crackled texture, made by me. CC0
Source Sojan Janso
A seamless pattern drawn originally in Paint.net by distorting a slice of background pattern 116 and copying the resulting triangle numerous times.
Source Firkin
Remixed from a drawing in 'Incidents on a Journey through Nubia to Darfoor', F. Ensor, 1891.
Source Firkin
The name is totally random, but hey, it sounds good.
Source Atle Mo
Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
More in the paper realm, this time with fibers.
Source Jorge Fuentes
The tile this is formed from can be retrieved in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
Here's a brown background pattern with subtle stripes. I hope you'll like the color. If not, feel free to change it using an image editor, if you know how of course. Personally, I'm using GIMP to create these backgrounds.
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
I’m not going to lie – if you submit something with the words Norwegian and Rose in it, it’s likely I’ll publish it.
Source Fredrik Scheide