The image depicts an edo-era pattern called "same-komon" or "鮫小紋"which looks like a shark skin.The "same" in Japanese means shark in English.
Source Yamachem
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
CC0 and seamless wellington boot pattern.
Source SliverKnight
Prismatic Geometric Tessellation Pattern 3 No Background
Source GDJ
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
I scanned a paper coffee cup. You know, in case you need it.
Source Atle Mo
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Number 3 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Abstract Background Design No Black
Source GDJ
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
The name is totally random, but hey, it sounds good.
Source Atle Mo
A large pattern with funky shapes and form. An original. Sort of origami-ish.
Source Luuk van Baars
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin