Honestly, who does not like a little pipe and mustache?
Source Luca Errico
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I. A version of the original with random colors.
Source Firkin
A dark striped seamless pattern suitable for use as a background on websites.
Source V. Hartikainen
Here's a camo print with more tan and less green, such as might be used in a desert scenario. This is tileable, so it can be used as a wallpaper or background.
Source Eady
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 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Free tiled background with colorful stripes and white splatter.
Source V. Hartikainen
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Background Wall, Art Abstract, Blue Well & CC0 texture.
Source Ractapopulous
Used the 6th circle pattern designed by Viscious-Speed to create a print that can be used for card making or scrapbooking. Save as a PDF file for the best printing option.
Source Lovinglf
A pattern derived from part of a fractal rendering in Paint.net.
Source Firkin
Could be paper, could be a Polaroid frame – up to you!
Source Chaos
This seamless background image should look nice on websites. It has a dark blue gray texture with vertical stripes, it tiles seamlessly and, like all of the background images here, it's free. So, if you like it, take it!
Source V. Hartikainen
A repeating background with wood/straw like texture.
Source V. Hartikainen
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
Colored maple leaves scattered on a surface. This is tileable, so it can be used as a background or wallpaper.
Source Eady
Remixed from a PNG that was uploaded to Pixabay by VictorianLady
Source Firkin
From an image on opengameart.org shared by rubberduck.
Source Firkin
Love the style on this one, very fresh. Diagonal diamond pattern. Get it?
Source INS
An emulated “transparent” background pattern, like that of all kinds of computer graphics software.
Source AdamStanislav
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Abstract Tiled Background Extended 11
Source GDJ
Prismatic Groovy Concentric Background 2 No Black
Source GDJ
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf