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
Here's a new paper-like background for free use on personal and commercial projects (this applies to all background patterns here).
Source V. Hartikainen
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
An emulated “transparent” background pattern, like that of all kinds of computer graphics software.
Source AdamStanislav
The image depicts a seamless pattern of a tortoise in tortoiseshell (hexagon).
Source Yamachem
Based on an image that was uploaded to Pixabay by devanath
Source Firkin
Sounds French. Some 3D square diagonals, that’s all you need to know.
Source Graphiste
Colour version that is close to the original drawing uploaded to Pixabay by pencilparker.
Source Firkin
Used in small doses, this could be a nice subtle pattern. Used on a large surface, it’s dirty!
Source Paul Reulat
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!
Source Dertig Media
A repeating graphic with ancient pattern. I came up with this name/title at last minute, so you may find that there is very little of ancientness in this pattern after all.
Source V. Hartikainen
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
Zero CC tileable ground (#2) cracked, crackled texture, made by me. CC0
Source Sojan Janso
A comeback for you: the popular Escheresque, now in black.
Source Patten
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Bit of a strange name on this one, but still nice. Tiny gray square things.
Source Carlos Valdez
A version without colours blended together to give a different look.
Source Firkin
Vertical lines with a bumpy, yet crisp, feel to it.
Source Raasa