Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
Coming in at 666x666px, this is an evil big pattern, but nice and soft at the same time.
Source Atle Mo
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
Nicely crafted paper pattern, although a bit on the large side (500x593px).
Source Blaq Annabiosis
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
A seamless background pattern with a texture of wood planks. This wood background pattern has vertically arranged planks. You may try to rotate it 90°, to see how it will look like when the wood planks are arranged horizontally.
Source V. Hartikainen
Remixed from a drawing that was uploaded to Pixabay by DavidZydd
Source Firkin
Seamless Prismatic Geometric Pattern With Background
Source GDJ
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
A cute x, if you need that sort of thing.
Source Juan Scrocchi
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
Almost like little fish shells, or dragon skin.
Source Graphiste
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
A repeating background of beige (or is it more vanilla yellow) textured stripes. One more background with stripes.
Source V. Hartikainen