Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I. Version with black background.
Source Firkin
Prismatic Abstract Geometric Background 2 No Black
Source GDJ
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Submitted in a cream color, but you know how I like it.
Source Devin Holmes
Derived from an image that was uploaded to Pixabay by darkmoon1968
Source Firkin
Colourful background achieved with gradient fills.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
It looks very nice I think.
Source V. Hartikainen
This seamless pattern consists of a blue grid on a yellow background.
Source V. Hartikainen
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
A seamless pattern of dark bricks. Maybe it's not very realistic, but it looks good in my opinion.
Source V. Hartikainen
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Geometric lines are always hot, and this pattern is no exception.
Source Listvetra
A white version of the very popular linen pattern.
Source Ant Ekşiler
Traced from a drawing in 'Household Stories from the Collection of the Brothers Grimm', Wilhelm Carl Grimm , 1882.
Source Firkin
A pale yellow background pattern with vertical stripes. The stripes are partially faded. I think this background image turned out pretty well, especially those faded stripes.
Source V. Hartikainen
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars