Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
Original minus the background
Source Firkin
Prismatic Triangular Seamless Pattern III With Background
Source GDJ
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Some rectangles, a bit of dust and grunge, plus a hint of concrete.
Source Atle Mo
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
Remixed from a drawing in 'Очерки Русской Исторіи въ памятникахъ быта', Petr Polevoi, 1879.
Source Firkin
A re-make of the Gradient Squares pattern.
Source Dimitar Karaytchev
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
A dark striped seamless pattern suitable for use as a background on websites.
Source V. Hartikainen
Oh yes, it happened! A pattern in full color.
Source Atle Mo
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Some dark 45 degree angles creating a nice pattern. Huge.
Source Dark Sharp Edges
Abstract Ellipses Background Grayscale
Source GDJ
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
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