Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
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 comeback for you: the popular Escheresque, now in black.
Source Patten
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
A free repetitive background with a dark concrete wall like texture. This one may be used in dark web site designs.
Source V. Hartikainen
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
Remixed from a drawing in 'A Child of the Age', Francis Adams, 1894.
Source Firkin
Floral patterns might not be the hottest thing right now, but you never know when you need it!
Source Lauren
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
Semi-light fabric pattern made out of random pixels in shades of gray.
Source Atle Mo
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Number five from the same submitter, makes my job easy.
Source Dima Shiper
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Did some testing with Repper Pro tonight, and this gray mid-tone pattern came out.
Source Atle Mo
From a drawing in 'Less Black than we're painted', James Payn, 1884.
Source Firkin
A free background pattern with abstract green tiles.
Source V. Hartikainen
From a drawing in 'Hubert Montreuil, or the Huguenot and the Dragoon', Francisca Ouvry, 1873.
Source Firkin
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
White circles connecting on a light gray background.
Source Mark Collins