Zero CC tileable yellow craft paper; scanned and made by me. CC0
Source Sojan Janso
The following orange background pattern resembles a honeycomb.
Source V. Hartikainen
The tile this is based on was adapted from an image that was uploaded to Pixabay by frolicsomepl. It can be had in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
This is a semi-dark pattern, sort of linen-y.
Source Sagive SEO
ZeroCC tileable mossy (lichen) stone texture, edited from pixabay. CC0
Source Sojan Janso
Zero CC tileable grass texture, photographed and made by me. CC0
Source Sojan Janso
A seamless web background with texture of aged grid paper.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.
Source Simon Meek
Zero CC bark from fur tree tileable texture, photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Alternative colour scheme. 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
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
Non-seamless pattern drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
This seamless background image should look nice on websites. It has a dark blue gray texture with vertical stripes, it tiles seamlessly and, like all of the background images here, it's free. So, if you like it, take it!
Source V. Hartikainen
A pattern drawn in Paint.net and vectorized in Vector Magic.
Source Firkin