This one is so simple, yet so good. And you know it. Has to be in the collection.
Source Gluszczenko
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Heavily remixed from a drawing that was uploaded to Pixabay by ractapopulous
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A dark striped seamless pattern suitable for use as a background on websites.
Source V. Hartikainen
Seamless Prismatic Geometric Pattern With Background
Source GDJ
An orange vertically striped background pattern. Feel free to download and use this orange background pattern, for example, on the web). It resembles a wallpaper with vertical stripes or something similar to it.
Source V. Hartikainen
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Wild Oliva or Oliva Wilde? Darker than the others, sort of a medium dark pattern.
Source Badhon Ebrahim
A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A free seamless background pattern for use on websites.
Source V. Hartikainen
This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
Prismatic Rounded Squares Grid 4 No Background
Source GDJ
The image is a seamless pattern of a fishnet.
Source Yamachem
Prismatic Geometric Tessellation Pattern No Background
Source GDJ
Remix from a drawing in 'Ostatnie chwile powstania styczniowego', Zygmunt Sulima, 1887.
Source Firkin
The image depicts a seamless pattern which was made using stripe-like things including borders.I used OCAL cliparts called "Blue Greek Key With Lines Border" uploaded by "GR8DAN" and "daisy border" uploaded by "johnny_automatic".Thanks.
Source Yamachem
Might not be super subtle, but quite original in its form.
Source Alex Smith
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
A hint of orange color, and some crossed and embossed lines.
Source Adam Anlauf
Prismatic Abstract Geometric Background 2 No Black
Source GDJ