A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Utilising a bird from s-light and some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
The tile for this is based on a repeating unit close to a design on Pixabay. It can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
Classy golf-pants pattern, or crossed stripes if you will.
Source Will Monson
Derived from a corner decoration itself found as a jpg on Pixabay.
Source Firkin
Prismatic Abstract Geometric Background 4
Source GDJ
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
A very dark asfalt pattern based off of a photo taken with my iPhone.
Source Atle Mo
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
Remixed from a drawing in 'Jezebel's Daughter', Wilkie Collins 1880
Source Firkin
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
Prismatic Abstract Background Design No Black
Source GDJ
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
This is sort of fresh, but still feels a bit old school.
Source Martuchox
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
One more in the line of patterns inspired by Japanese/Asian styles. Smooth.
Source Kim Ruddock
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A repeating background with seamless texture of stone. There haven't been any stone-like backgrounds for a while, so I have decided to create one more. The rest can be found in the appropriate category.
Source V. Hartikainen
Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic