Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
CC0 remixed from a drawing. Walter Crane, 1914, Firkin.
Source SliverKnight
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
The image a seamless pattern derived from a weed which I can't identify.The original weed image is from here:https://jp.pinterest.com/pin/500744052301423641/
Source Yamachem
People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
Prismatic Curved Diamond Pattern 2 No Background
Source GDJ
Seamless Green Tile Background
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
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This reminds me of Game Cube. A nice light 3D cube pattern.
Source Sander Ottens
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
Colour version of the original pattern.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
You know I love paper patterns. Here is one from Stephen. Say thank you!
Source Stephen Gilbert
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
A large pattern with funky shapes and form. An original. Sort of origami-ish.
Source Luuk van Baars
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning