A simple but elegant classic. Every collection needs one of these.
Source Christopher Burton
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
A simple bump filter made upon request at irc #inkscape at freenode. Made a screen capture of the making here: https://youtu.be/TGAWYKVLxQw
Source Lazur URH
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
A seamless pattern based on a rectangular tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
From a drawing in 'Artists and Arabs', Henry Blackburn, 1868
Source Firkin
Background Wall, Art Abstract, Star Well & CC0 texture.
Source Ractapopulous
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
Three shades of gray makes this pattern look like a small carbon fiber surface. Great readability even for small fonts.
Source Atle Mo
A version without colours blended together to give a different look.
Source Firkin
Uses spirals from Pixabay. To get the basic tile select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Same classic 45-degree pattern, dark version.
Source Luke McDonald
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This is the remix of an OCAL clipart called "Rain on Window" uploaded by "pagarmidna".Thanks.This is a seamless pattern of raindrops.
Source Yamachem
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
Abstract Tiled Background Extended 10
Source GDJ
A textured orange background pattern with vertical stripes.
Source V. Hartikainen
An alternative colour scheme to the original seamless pattern.
Source Firkin