The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
You may use it as is, or modify it as you like.
Source V. Hartikainen
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
Have you wondered about how it feels to be buried alive? Here is the pattern for it.
Source Hendrik Lammers
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
Real snow that tiles, not easy. This is not perfect, but an attempt.
Source Atle Mo
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
I love the movie Pineapple Express, and I’m also liking this Pineapple right here.
Source Audee Mirza
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Not so subtle. These tileable wood patterns are very useful.
Source Elemis
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
This one is so simple, yet so good. And you know it. Has to be in the collection.
Source Gluszczenko
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
A fun-looking elastoplast/band-aid pattern. A hint of orange tone in this one.
Source Josh Green
From a drawing in 'Royal Ramsgate', James Simson, 1897.
Source Firkin
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
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
Zero CC tileable dry grass texture, photographed and made by me. CC0
Source Sojan Janso
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Prismatic Abstract Geometric Background 5 No Black
Source GDJ
From a drawing in 'Friend or Fortune? The story of a strange year', Robert Overton, 1897.
Source Firkin
Prismatic Floral Background No Black
Source GDJ