A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
This background image has seamless texture that resembles a surface of gray stone.
Source V. Hartikainen
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
This one is super crisp at 2X. Lined paper with some dust and scratches.
Source HQvectors
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
Floral patterns might not be the hottest thing right now, but you never know when you need it!
Source Lauren
Prismatic Polka Dots Mark II 3 No Background
Source GDJ
From a drawing in 'Az Osztrák-Magyar Monarchia irásban és képben', 1885.
Source Firkin
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne
Zero CC tileable grass texture, photographed and made by me. CC0
Source Sojan Janso
A free black metallic background pattern. Here's a new pattern I made that looks metallic.
Source V. Hartikainen
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Lovely pattern with splattered vintage speckles.
Source David Pomfret
Psychedelic Geometric Background No Black
Source GDJ
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Zero CC tileable hard cover green book, scanned and made by me. CC0
Source Sojan Janso
A lovely light gray pattern with stripes and a dash of noise.
Source V. Hartikainen
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
We have some linen patterns here, but none that are stressed. Until now.
Source Jordan Pittman
Remixed from a vector adapted from a jpg on Pixabay. The tile this is constructed from can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A seamless pattern formed from miutopia mug remixes on a tablecloth.
Source Firkin