A seamless pattern formed from a tile made from page ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless pattern of dark bricks. Maybe it's not very realistic, but it looks good in my opinion.
Source V. Hartikainen
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin
A brown seamless wood texture in a form of stripe pattern. The result has turned out pretty well, in my opinion.
Source V. Hartikainen
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Alternative colour scheme. 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
CC0 remixed from a drawing. Walter Crane, 1914, Firkin.
Source SliverKnight
Same as Silver Scales, but in black. Turn your site into a dragon with this great scale pattern.
Source Alex Parker
Prismatic Geometric Pattern Variation 2 With Background
Source GDJ
Prismatic Curved Diamond Pattern 3 No Background
Source GDJ
Otis Ray Redding was an American soul singer-songwriter, record producer, arranger, and talent scout. So you know.
Source Thomas Myrman
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Oh yes, it happened! A pattern in full color.
Source Atle Mo
An abstract texture of water. It's not perfect, but will do. You may download if you like it.
Source V. Hartikainen
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
Inspired by a pattern found in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
From a drawing in 'Prose and Verse ', William Linton, 1836.
Source Firkin
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
Zero CC tileable moss or lichen covered stone texture, edited from pixabay. CC0
Source Sojan Janso
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin