CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
A seamless background pattern with impressed gray dots.
Source V. Hartikainen
From a drawing in 'Worsborough; its historical associations and rural attractions', Joseph Wilkinson, 1879.
Source Firkin
The name tells you it has curves. Oh yes, it does!
Source Peter Chon
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
Colour version that is close to the original drawing uploaded to Pixabay by pencilparker.
Source Firkin
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
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 Hexagonalist Pattern No Background
Source GDJ
Seamless Prismatic Geometric Pattern With Background
Source GDJ
Prismatic Polyskelion Pattern No Background
Source GDJ
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A seamless texture of an abstract wall colored in shades of light orange brown.
Source V. Hartikainen
Prismatic Groovy Concentric Background 2 No Black
Source GDJ
Colour version that is close to the original drawing uploaded to Pixabay by pencilparker.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin