From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Non-seamless pattern drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Pixel by pixel, sharp and clean. Very light pattern with clear lines.
Source M.Ashok
Remixed from a PNG that was uploaded to Pixabay by gingertea
Source Firkin
A white version of the very popular linen pattern.
Source Ant Ekşiler
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
Prismatic Abstract Background Design
Source GDJ
Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
One week and it's Easter already. Thought I would revisit the decorated egg contest at inkscape community: http://forum.inkscapecommunity.com/index.php?topic=118.0
Source Lazur URH
This was formed by distorting an image of a background on Pixabay.
Source Firkin
A seamless paper background colored in pale yellow.
Source V. Hartikainen
Prismatic Polyskelion Pattern No Background
Source GDJ
One more from Badhon, sharp horizontal lines making an embossed paper feeling.
Source Badhon Ebrahim
Super simple but very nice indeed. Gray with vertical stripes.
Source Merrin Macleod
This is lovely, just the right amount of subtle noise, lines and textures.
Source Richard Tabor
The image depicts a seamless pattern of Japanese Edo pattern called "kikkou-matsu" or "亀甲松" meaning " tortoiseshell-pinetree".The real pinetree is like this: https://jp.pinterest.com/pin/500744052301065077/
Source Yamachem
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Zero CC tileable bark texture, photographed and made by me. CC0
Source Sojan Janso
Prismatic Snowflakes 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
I skipped number 3, because it wasn’t all that great. Sorry.
Source Dima Shiper
This texture looks like old leather. It should look great as a background on web pages.
Source V. Hartikainen
Can’t believe we don’t have this in the collection already! Slick woven pattern with crisp details.
Source Max Rudberg