This could be a hippy vintage wallpaper.
Source Tileable Patterns
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
To get the repeating unit, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
Prismatic Geometric Pattern Background 2 No Black
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
This light background pattern has a texture of "frozen" surface with diagonal stripes. Here's an yet another addition to the collection of free website backgrounds.
Source V. Hartikainen
You know you love wood patterns, so here’s one more.
Source Richard Tabor
Prismatic Abstract Geometric Background 2
Source GDJ
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
Number 4 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
A bit strange this one, but nice at the same time.
Source Diogo Silva
Three shades of gray makes this pattern look like a small carbon fiber surface. Great readability even for small fonts.
Source Atle Mo
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
Prismatic Rounded Squares Grid 4 No Background
Source GDJ
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
As the original image 's page size is too large for its image size, I remixed it.
Source Yamachem
Bright Multicolored Floral Background by Karen Arnold from PDP.
Source GDJ
A seamless pattern created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.
Source Firkin