Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Little x’es, noise and all the stuff you like. Dark like a Monday, with a hint of blue.
Source Tom McArdle
The image depicts a seamless pattern of Japanese Edo pattern called "kikkou-matsu" or "亀甲松" meaning " tortoiseshell-pinetree".The real pinetree is like this: https://jp.pinterest.com/pin/500744052301065077/
Source Yamachem
A free seamless background with pink spots.
Source V. Hartikainen
Continuing the geometric trend, here is one more.
Source Mike Warner
A grayscale fabric pattern with vertical lines of stitch holes.
Source V. Hartikainen
Utilising a bird from s-light and some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
A seamless pattern made from the gold Penrose triangle by GDJ and the two remixes
Source Firkin
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
A pattern drawn in Paint.net and vectorized in Vector Magic.
Source Firkin
Prismatic 3D Isometric Tessellation Pattern 6
Source GDJ
Prismatic Polka Dots 3 No Background
Source GDJ
Fabric-ish patterns are close to my heart. French Stucco to the rescue.
Source Christopher Buecheler
A blue gray fabric-like texture for websites. An yet another fabric-like texture. It has subtle vertical and diagonal stripes to it.
Source V. Hartikainen
The image depicts a seamless pattern of a Japanese family crest called "chidori" in Japanese .A chidori in Japanese means a plover in English.
Source Yamachem
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
Here's a repeatable texture that resembles a light green concrete wall or something similar.
Source V. Hartikainen
A free pink background pattern.
Source V. Hartikainen
Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas