This is indeed a bit strange, but here’s to the crazy ones!
Source Christopher Buecheler
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Background pattern originally a PNG drawn in Paint.net
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
The tile can be had by selecting the rectangle in Inkscape and using shift+alt+i. Remixed from a drawing in 'Flowers of Song', Frederick Weatherly, 1895.
Source Firkin
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
Prismatic Abstract Geometric Background derived from an image on Pixabay.
Source GDJ
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Submitted in a cream color, but you know how I like it.
Source Devin Holmes
Remixed from a drawing in 'Canadian forest industries July-December', 1915
Source Firkin
Derived from a drawing in 'Elfrica. An historical romance of the twelfth century', Charlotte Boger, 1885
Source Firkin
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Colour version that is close to the original drawing uploaded to Pixabay by pencilparker.
Source Firkin
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Never out of fashion and so much hotter than the 45º everyone knows, here is a sweet 60º line pattern.
Source Atle Mo
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Remixed from a drawing in 'A Child of the Age', Francis Adams, 1894.
Source Firkin
ZeroCC tileabel stone granite texture, edited from pixabay. CC0
Source Sojan Janso
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
That’s what it is, a dark dot. Or sort of carbon looking.
Source Tsvetelin Nikolov
Derived from an image that was uploaded to Pixabay by darkmoon1968
Source Firkin