This was formed by distorting an image of a background on Pixabay.
Source Firkin
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A criss-cross pattern similar to one I saw mown into a sports field.
Source Firkin
Prismatic Polka Dots Mark II 2 No Background
Source GDJ
From a drawing in 'Prose and Verse ', William Linton, 1836.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Pixel by pixel, sharp and clean. Very light pattern with clear lines.
Source M.Ashok
Dark Tile-able Grunge Texture. I think this texture can be classified as grunge. It's free and seamless, as always.
Source V. Hartikainen
A seamless pattern formed from cross 4. To get the original tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Super dark, crisp and detailed. And a Kill Bill reference.
Source Badhon Ebrahim
Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern
Source Firkin
Number 3 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Remixed from a raster on Pixabay, that was uploaded by ArtsyBee.
Source Firkin
From a drawing in 'Uit de geschiedenis der Heilige Stede te Amsterdam', Yohannes Sterck, 1898.
Source Firkin
Subtle scratches on a light gray background.
Source Andrey Ovcharov
Geometric triangles seem to be quite hot these days.
Source Pixeden
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I. Version with black background.
Source Firkin
Prismatic 3D Isometric Tessellation Pattern 6
Source GDJ