As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
A pale olive green background with a seamless texture.
Source V. Hartikainen
Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Derived from a corner decoration itself found as a jpg on Pixabay.
Source Firkin
From a drawing in 'Hundert Jahre in Wort und Bild', S. Stefan, 1899.
Source Firkin
Inspired by a pattern seen on a public domain image of a very old tile. To get the unit cell, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
Imagine you zoomed in 1000X on some fabric. But then it turned out to be a skeleton!
Source Angelica
Prismatic Polyskelion Pattern No Background
Source GDJ
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Seamless Olive Green Web Background Image
Source V. Hartikainen
The classic notebook paper with horizontal stripes.
Source Are Sundnes
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
Seamless pattern the basic tile for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers
The following repeating website background is colored in a blue gray color and resembles a concrete wall or something similar to it.
Source V. Hartikainen
A very slick dark rubber grip pattern, sort of like the grip on a camera.
Source Sinisha
Prismatic 3D Isometric Tessellation Pattern 6
Source GDJ
A pattern derived from part of a fractal rendering in Paint.net.
Source Firkin
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
Inspired by a pattern I saw in a 19th century book. This seamless pattern was created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo