Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Tweed is back in style – you heard it here first. Also, the @2X version here is great!
Source Simon Leo
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Classy golf-pants pattern, or crossed stripes if you will.
Source Will Monson
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.
Source Firkin
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
The image depicts a seamless pattern of the design which includes a stylized lotus and a stylized crane.I referred to the original image in a book which is into public domain.
Source Yamachem
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
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
Prismatic Geometric Pattern Background No Black
Source GDJ
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin