A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
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
Prismatic Abstract Background Design No Black
Source GDJ
Remixed from a raster on Pixabay that was uploaded by ArtsyBee.
Source Firkin
A new take on the black linen pattern. Softer this time.
Source Atle Mo
Prismatic Geometric Pattern Background 2 No Black
Source GDJ
The original enhanced with one of Inkscapes's filters.
Source Firkin
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Prismatic Triangular Background Design Mark II 5
Source GDJ
Zero CC tileable yellow craft paper; scanned and made by me. CC0
Source Sojan Janso
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
This is the remix of an OCAL clipart called "Art Nouveau ornament" uploaded by "microcosme".Thanks.This is a seamless pattern of an Art Nouveau ornament.
Source Yamachem
A light brushed aluminum pattern for your pleasure.
Source Tim Ward
"Beige Stone", Tileable Texture.
Source V. Hartikainen
The classic subtle pattern. Sort of wall/brick looking. Or moon-looking?
Source Joel Klein
Fake or not, it’s quite luxurious.
Source Factorio.us Collective
A classic dark tile for a bit of vintage darkness.
Source Listvetra
A nice and simple gray stucco material. Great on its own, or as a base for a new pattern.
Source Bartosz Kaszubowski
A free pink background pattern.
Source V. Hartikainen