Not so subtle. These tileable wood patterns are very useful.
Source Elemis
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
White circles connecting on a light gray background.
Source Mark Collins
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
The name Paisley reminds me of an old British servant. That’s just me.
Source Swetha
Hey, you never know when you’ll need a bird pattern, right?
Source Pete Fecteau
Another fairly simple design drawn in Paint.net and vectorized in Inkscape.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
One more in the line of patterns inspired by Japanese/Asian styles. Smooth.
Source Kim Ruddock
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
Light gray paper pattern with small traces of fiber and some dust.
Source Atle Mo
Prismatic Abstract Geometric Background 4
Source GDJ
From a drawing in 'Worsborough; its historical associations and rural attractions', Joseph Wilkinson, 1879.
Source Firkin
A very slick dark rubber grip pattern, sort of like the grip on a camera.
Source Sinisha
Prismatic Geometric Pattern Background 2
Source GDJ
A nice and simple white rotated tile pattern.
Source Another One
Might not be super subtle, but quite original in its form.
Source Alex Smith