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
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!
Source Dertig Media
An emulated “transparent” background pattern, like that of all kinds of computer graphics software.
Source AdamStanislav
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Triangular Seamless Pattern III With Background
Source GDJ
From a drawing in 'Az Osztrák-Magyar Monarchia irásban és képben', 1885.
Source Firkin
Sharp diamond pattern. A small 24x18px tile.
Source Tom Neal
A seamless textured paper for backgrounds. Colored in pale orange hues.
Source V. Hartikainen
Inspired by a JPG that was uploaded to Pixabay by kokon_art
Source Firkin
First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.
Source Atle Mo
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
Inspired by a drawing in 'Kulturgeschichte', Freidrich Hellwald, 1896.
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Inspired by a drawing in 'Poems', James Smith, 1881.
Source Firkin
Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
This could be a hippy vintage wallpaper.
Source Tileable Patterns
A seamless pattern with a unit cell drawn as a bitmap in Paint.net and vectorized in Vector Magic.
Source Firkin
I love these crisp, tiny, super subtle patterns.
Source Badhon Ebrahim
From a drawing of the coat of arms of the Ottoman Empire on Wikimedia.
Source Firkin
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
Pattern produced in Paint.net using the Vibrato plug-in.
Source Firkin