A pattern drawn in Paint.net and vectorized in Vector Magic.
Source Firkin
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
Derived from a PNG that was uploaded to Pixabay by nutkitten
Source Firkin
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
Fix and cc0 to get the tile this is based on.
Source SliverKnight
From a drawing in 'Az Osztrák-Magyar Monarchia irásban és képben', 1885.
Source Firkin
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
A heavy hitter at 400x400px, but lovely still.
Source Breezi
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
A repeatable image with dark background and metal grid pattern.
Source V. Hartikainen
Colourful background achieved with gradient fills.
Source Firkin
ZeroCC tileabel stone granite texture, edited from pixabay. CC0
Source Sojan Janso
Tweed is back in style – you heard it here first. Also, the @2X version here is great!
Source Simon Leo
Psychedelic Geometric Background No Black
Source GDJ
That’s what it is, a dark dot. Or sort of carbon looking.
Source Tsvetelin Nikolov
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
Prismatic Geometric Pattern Background 2
Source GDJ
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
Number 5 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Prismatic Abstract Geometric Background 4
Source GDJ
Zero CC tileable cork floor, photographed and made by me. CC0
Source Sojan Janso
A criss-cross pattern similar to one I saw mown into a sports field.
Source Firkin
Prismatic Abstract Geometric Background 5 No Black
Source GDJ