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
Scanned some rice paper and tiled it up for you. Enjoy.
Source Atle Mo
From a drawing in 'Handbook of the excursions proposed to be made by the Lincoln Diocesan Architectural Society, on the 27th and 28th of May, 1857', Edward Trollope, 1857.
Source Firkin
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
Brushed aluminum, in a bright gray version. Lovely 2X as well.
Source Andre Schouten
Remixed from a drawing in 'Works. Popular edition', John Ruskin, 1886.
Source Firkin
A seamless pattern formed from cross 4. To get the original tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Prismatic Geometric Tessellation Pattern 2 No Background
Source GDJ
To celebrate the new feature, we need some sparkling diamonds.
Source Atle Mo
Derived from a drawing in 'Elfrica. An historical romance of the twelfth century', Charlotte Boger, 1885
Source Firkin
Remixed from a drawing in 'Kulturgeschichte der Deutschen im Mittelalter' Franz von Loeher, 1891. The unit tile can be had by selecting the rectangle in Inkscape and using shift-alt-i
Source Firkin
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin
Prismatic Geometric Tessellation Pattern 3 No Background
Source GDJ
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Here's a camo print with more tan and less green, such as might be used in a desert scenario. This is tileable, so it can be used as a wallpaper or background.
Source Eady
Bright Multicolored Floral Background by Karen Arnold from PDP.
Source GDJ
A textured blue background pattern with vertical stripes.
Source V. Hartikainen