A free seamless background image with a texture of dark red "canvas". It should look very nice on web sites.
Source V. Hartikainen
A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.
Source Lazur URH
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857
Source Firkin
Remixed from a drawing in 'An Index to Deering's Nottinghamia Vetus et Nova', Rupert Chicken, 1899. The unit tile can be had by selecting the rectangle in Inkscape and using shift-alt-i
Source Firkin
Sharp diamond pattern. A small 24x18px tile.
Source Tom Neal
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A beautiful dark padded pattern, like an old classic sofa.
Source Chris Baldie
This reminds me of Game Cube. A nice light 3D cube pattern.
Source Sander Ottens
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Background Wall, Art Abstract, white Well & CC0 texture.
Source Ractapopulous
Here's an yet another seamless note paper texture for use as a background on websites.
Source V. Hartikainen
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
Just like the black maze, only in light gray. Duh.
Source Peax
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
A light brushed aluminum pattern for your pleasure.
Source Tim Ward
Original seamless pattern with an Inkscape filter.
Source Firkin
Colourful background achieved with gradient fills.
Source Firkin
A repeating gloomy background image. This one consists of a pattern of black chains layered on top of a dark textured background.
Source V. Hartikainen
This was formed by distorting an image of a background on Pixabay.
Source Firkin