CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
A new take on the black linen pattern. Softer this time.
Source Atle Mo
This is indeed a bit strange, but here’s to the crazy ones!
Source Christopher Buecheler
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Pass parameters to the URL or edit the source code variables to configure the graph paper for the division desired.
Source JayNick
Derived from a PNG that was uploaded to Pixabay by nutkitten
Source Firkin
A seamless stone-like background for blogs or any other type of websites.
Source V. Hartikainen
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Prismatic Abstract Geometric Background 2
Source GDJ
This one looks like a cork panel. Feel free to use it as a tiled background on your blog or website.
Source V. Hartikainen
This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
A large pattern with funky shapes and form. An original. Sort of origami-ish.
Source Luuk van Baars
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
Smooth Polaroid pattern with a light blue tint.
Source Daniel Beaton
From a drawing in 'From Snowdon to the Sea. Striking stories of North and South Wales', Marie Trevelyan, 1895.
Source Firkin
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
From a drawing in 'Less Black than we're painted', James Payn, 1884.
Source Firkin
The texture of this background image has some similarities with leather, and it's colored in a dark brown color. So, if you are looking for a dark brown background image for your website, this may be an option for you.
Source V. Hartikainen
Inspired by a pattern I saw in a 19th century book. This seamless pattern was created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
Same classic 45-degree pattern, dark version.
Source Luke McDonald
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Real snow that tiles, not easy. This is not perfect, but an attempt.
Source Atle Mo