A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.
Source Firkin
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
Derived from an image that was uploaded to Pixabay by TheDigitalArtist
Source Firkin
A seamless web texture of "green stone".
Source V. Hartikainen
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
The name tells you it has curves. Oh yes, it does!
Source Peter Chon
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
Square design drawn in Paint.net and vectorized in Vector Magic.
Source Firkin
Background formed from the original with an emboss effect
Source GDJ
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
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
Did anyone say The Hoff? This pattern is in no way related to Baywatch.
Source Josh Green
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Prismatic Groovy Concentric Background 3
Source GDJ
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin