Sort of reminds me of those old house wallpapers.
Source Tish
Prismatic Geometric Pattern Background
Source GDJ
Remixed from a raster on Pixabay, that was uploaded by ArtsyBee.
Source Firkin
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Super detailed 16×16 tile that forms a beautiful pattern of straws.
Source Pavel
Prismatic Abstract Geometric Background 2
Source GDJ
Retro Circles Background 5 No Black
Source GDJ
This background pattern looks like bamboo to me. Feel free to download it for your website (for your blog perhaps?).
Source V. Hartikainen
Prismatic Triangular Seamless Pattern III With Background
Source GDJ
Colour version of the original pattern.
Source Firkin
From a drawing in 'Heroes of North African Discovery', Nancy Meugens, 1894.
Source Firkin
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Same as the black version, but now in shades of gray. Very subtle and fine grained.
Source Atle Mo
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin