The edges of all the red objects line up either vertically or horizontally, but it doesn't appear so. Made from a square tile that can be got by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Abstract Geometric Background 5 No Black
Source GDJ
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
There are quite a few grid patterns, but this one is a super tiny grid with some dust for good measure.
Source Dominik Kiss
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin
Actually, there's no clouds in it, but I think it looks quite nice.
Source V. Hartikainen
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Here is a new seamless wood texture for using as blog or website backgrounds.
Source V. Hartikainen
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
A free repetitive background with a dark concrete wall like texture. This one may be used in dark web site designs.
Source V. Hartikainen
White handmade paper pattern with small bumps.
Source Marquis
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
Here's a quite bright pink background pattern for use on websites. It doesn't look like a real fur, but it definitely resembles one.
Source V. Hartikainen
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
A free tileable background colored in off-white (antique white) color.
Source V. Hartikainen
A repeating graphic with ancient pattern. I came up with this name/title at last minute, so you may find that there is very little of ancientness in this pattern after all.
Source V. Hartikainen
Nicely crafted paper pattern, although a bit on the large side (500x593px).
Source Blaq Annabiosis
Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Super dark, crisp and detailed. And a Kill Bill reference.
Source Badhon Ebrahim
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin