This could be a hippy vintage wallpaper.
Source Tileable Patterns
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf
A seamless pattern with green and yellow diagonal lines on top of a white dotted background.
Source V. Hartikainen
A mid-tone gray pattern with some cement looking texture.
Source Hendrik Lammers
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Prismatic Geometric Tessellation Pattern 2 No Background
Source GDJ
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
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
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
Drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Coming in at 666x666px, this is an evil big pattern, but nice and soft at the same time.
Source Atle Mo
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A background tile for web with abstract repeating texture of dark "stone wall".
Source V. Hartikainen
Vertical lines with a bumpy, yet crisp, feel to it.
Source Raasa
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
This is the remix of an OCAL clipart called "Art Nouveau ornament" uploaded by "microcosme".Thanks.This is a seamless pattern of an Art Nouveau ornament.
Source Yamachem
A seamlessly tile-able grunge background image.
Source V. Hartikainen
Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
From a drawing in 'Danmarks Riges Historie af J. Steenstrup, Kr. Erslev, A. Heise, V. Mollerup, J. A. Fridericia, E. Holm, A. D. Jørgensen', 1897.
Source Firkin
Zero CC tileable hard cover cells, skin like, book texture. 4K, Scanned and made by me CC0
Source Sojan Janso
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin