I guess this is inspired by the city of Ravenna in Italy and its stone walls.
Source Sentel
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin
I love these crisp, tiny, super subtle patterns.
Source Badhon Ebrahim
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
This is the remix of an OCAL clipart called "Rain on Window" uploaded by "pagarmidna".Thanks.This is a seamless pattern of raindrops.
Source Yamachem
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
A simple circle. That’s all it takes. This one is even transparent, for those who like that.
Source Saqib
A repeating background for websites with a texture of black groove stripes.
Source V. Hartikainen
Bigger is better, right? So here you have some large carbon fiber.
Source Factorio.us Collective
A nice and simple gray stucco material. Great on its own, or as a base for a new pattern.
Source Bartosz Kaszubowski
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Pattern Background, Texture, Photoshop Structure style CC0 texture.
Source Darkmoon1968
Has nothing to do with toast, but it’s nice and subtle.
Source Pippin Lee
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
Real snow that tiles, not easy. This is not perfect, but an attempt.
Source Atle Mo
Prismatic Snowflakes Pattern 2 No Background
Source GDJ
A lovely light gray pattern with stripes and a dash of noise.
Source V. Hartikainen
A seamless pattern with green and yellow diagonal lines on top of a white dotted background.
Source V. Hartikainen
Colorful Floral Background No Black
Source GDJ
This one has rusty dark brown texture.
Source V. Hartikainen